COMMONL Y ENCOUNTERED REGIONAL INJURIES Shoulder

COMMONL Y ENCOUNTERED REGIONAL INJURIES Shoulder

Shoulder instability and rotator cuff tear Background Shoulder injuries a ff ect athletes of all ages; however, the distribution of shoulder injuries varies between young and Rudolph Grashey , 1876–1950, Professor of Roentgenology , University of Cologne, Cologne, Germany . Alfred-Armand-Louis-Marie Velpeau , 1795–1867, French anatomist and surgeon. Harold Arthur Hill , 1901–1973, radiologist, San Francisco, CA, USA. Maurice David Sachs , 1909–1987, radiologist, San Francisco, CA, USA. older participants. In athletes younger than 30 years old, espe - cially those participating in contact sports, anterior shoulder dislocations can occur in instances of traumatic or forced shoulder abduction and external rotation. Unfortunately , such dislocations, even if r educed, lead to some degree of stretch - ing of the anterior capsule and tearing of the anteroinferior labrum, which places the patient at risk for further instability events. In older patients who experience falls and sustain the same anterior shoulder dislocations, additional pathologies, including rotator cu ff tears , can occur. History and physical examination Patients who sustain a shoulder dislocation often describe a violent injury event such as a fall or tackle with the arm in some degree of abduction. Patients will often describe a sensation of their shoulder feeling out of place, especially if - the shoulder does not spontaneously reduce. An important component of the history involves the details of the disloca - tion(s): self-reduction versus emergency department reduction, length of time dislocated prior to reduction, prior dislocations, extremity numbness, general ligamentous laxity and activity profile – all of these details have implications for management. Examination in the acute period should focus on e valuating anterior apprehension or subjective patient discomfort and fear of re-dislocation in the positions of abduction and exter - nal rotation of the shoulder, as well as rotator cu ff strength and neurovascular integrity , especially of the axillary nerve (see 1,2 Further reading ). Imaging Radiographs, including at least true anteroposterior (AP) or Grashey , scapular Y , axillary or V elpeau views, should be obtained in all circumstances and evaluated to confirm glenohumeral reduction while ruling out associated fractures, such as Hill–Sachs deformities or glenoid rim fractures.

To assess the patient and offer treatment and • rehabilitation plans

Specific views, including the West Point axillary and the Stryker notch views, can be helpful for evaluating glenoid rim or Bankart fractures or Hill–Sachs lesions, respectively . In cases of recurrent instability where glenoid bone loss is suspected, computed tomography (CT) with or without three-dimensional reconstruction can be helpful in further determining the extent of bone loss. In most instances of anterior instability , magnetic resonance imaging (MRI) is recommended ( Figure 36.1 evaluate for concomitant soft-tissue injuries, including rotator cu ff tears, humeral avulsions of the glenohumeral ligament (HAGL), glenolabral articular disruptions (GLAD) or anterior labrum periosteal sleeve avulsion (ALPSA). Treatment After reduction of an acute anterior glenohumeral dislocation, patients are typically placed in a sling for the first few days. important to begin early gentle range of motion of the shoul der through pendulum exercises but also to continue to move the elbow , wrist and digits actively to maintain range of motion in those distal joints. The initial period is then progressed to increased passive and then active and active-assisted range of motion of the shoulder. Once range of motion has returned to near normal, rotator cu ff and scapular strengthening is progressed. Surgery is considered for even first-time dislo cators based upon stratification of several factors, including younger age, activity profile and pathology present on imag ing. Furthermore, depending upon the pathology present, the surgical options exist on a continuum fr om arthroscopic capsulolabral repair to open capsulolabral repair and capsular 3,4 shift to glenoid bony augmentation procedur es. Regardless of the treatment method chosen, athletes are cleared to return William Schamel Stryker , 1916–2015, orthopedic surgeon and Captain in the United States Navy . Arthur Sydney Blundell Bankart , 1879–1951, orthopaedic surgeon, The Middlesex Hospital, London, UK. to normal levels. Older athletes who acutely tear their rotator cu ff in the set - ting of shoulder dislocations can be considered for acute rota - 5 tor cu ff repair. The treatment of rotator cu ff tears has evolved over several years and current techniques of arthroscopic repair with a knotless, linked, double-row construct ( Figure 36.2 ) have demonstrated excellent patient-reported outcomes with low re-tear rates. Differential diagnosis /uni25CF Proximal humerus fracture. /uni25CF Greater tuberosity fracture. /uni25CF Acromioclavicular joint separation. Summary box 36.1 Shoulder instability /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF ) to 2 It is - - -

Anterior labral tear Figure 36.1 Axial /f_l uid-sensitive magnetic resonance image of the shoulder demonstrating an anterior labral tear. Dislocations occur in instances of traumatic or forced shoulder abduction and external rotation Details of the reduction, time dislocated, history of prior dislocations, general ligamentous laxity and activity pro /f_i le have implications for management Radiographs to con /f_i rm glenohumeral reduction include true AP or Grashey, scapular Y , axillary or Velpeau views A sling should be used for a few days following an acute anterior glenohumeral dislocation Surgery is considered based upon strati /f_i cation of several factors, including younger age, activity pro /f_i le and pathology present on imaging Rotator cuff tendon Suture anchor with repair sutures Figure 36.2 Shoulder arthroscopic image of a rotator cuff repair viewed from the subacromial space through a lateral portal with a 30° arthroscope.

Ulnar collateral ligament tear Background The anterior band of the ulnar collateral ligament (UCL) is the primary stabiliser to valgus stress at the elbow . Anatomi cally this ligament courses from the medial epicondyle of the humerus to the sublime tubercle of the ulna. Although it can be injured acutely through mechanisms of elbow dislocations, pathology is most frequently encountered in repetitive thro ing athletes, such as baseball pitchers and javelin throwers. In the late cocking and early acceleration phases of throwing the ligament is under its maximum stress and at this stage is at the highest risk of ruptur e and chronic attenuation. History and physical examination Throwers who sustain ruptures of their UCL commonly pres ent with two sets of complaints. Rarely , the thrower will recall an acute episode when they heard a pop in the throwing cycle followed by medial elbow pain and pain worse with throwing. The v ast majority of throwers complain of medial elbow pain and tightness coupled with decreased velocity that comes on more insidiously . Examination focuses on provocative manoeuvres that are specific for the UCL, including valgus stress and the moving valgus stress tests or milking manoeuvre ( Figure 36.3 ), in which the examiner provides a valgus stress 6 through elbow range of motion. Pain at the medial elbow during these manoeuvres is specific for UCL pathology . The examiner should also focus on both ulnar nerve sensory and motor symptoms in the hand in addition to ulnar nerve sublux ation as these pathologies can a ff ect the proposed treatment algorithm. Imaging Radiographs of the elbow include a series of AP , lateral, inter nal and external oblique views. These can help rule out other commonly encountered phenomena seen in overhead throwing athletes, including medial epicondyle fractures, posteromedial impingement and capitellar osteochondral defects. When UCL pathology is suspected, dynamic ultrasound is a helpful imaging modality to help characterise the loca tion of the UCL pathology . Moreover, it permits easy examination of the contralateral elbow , which can help to quantify incongruities in medial elbow joint space gapping, an indirect gauge of tear severity . MRI is commonly obtained to precisely define the location of the UCL tear as well as to better evaluate the articular cartilage and the flexor pronator mass, which can also commonly be a ff ected. Treatment Conservative management of UCL injuries is considered first line treatment and typically entails a period of several months of cessation of throwing followed by structured rehabilitation that includes strengthening of secondary stabilising muscles 6 about the elbow and a g radual return of throwing. The use of biological injections, including platelet-rich plasma, has been To m my Jo h n s u rge r y , named after Thomas Edward John Jr, the first major league baseball pitcher who received an ulnar collateral ligament reconstruction in 1974. - w - - proposed for partial-thickness ligament tears in some centres, but more clinical evidence is required. Although ligament repair with an internal brace has recently been demonstrated to have e ffi cacy in certain types of tears, the gold standard for surgical treatment is UCL reconstruction or Tommy John surgery . The surgery involves an autograft tendon harvest, commonly utilising the ipsilateral palmaris longus tendon, and reconstruction of the ligament through bone tunnels in - 6 both the humerus and ulna. This surgery can be coupled with in situ decompression or transposition of the ulnar nerve, if indicated. Ulnar reconstruction surgery is indicated for the highest level of throwers who wish to continue playing their respective sport, with return to sport taking anywhere from - 12 /uni00A0 to 18 months. Differential diagnosis /uni25CF Flexor pronator mass sprain. /uni25CF Ulnohumeral arthritis. /uni25CF Ulnar nerve compression or subluxation. /uni25CF Loose body . Summary box 36.2 UCL tears /uni25CF /uni25CF /uni25CF - /uni25CF /uni25CF

Examiner stabilises patient’s elbow Examiner pulls patient’s thumb with downward force Figure 36.3 Demonstration of the milking manoeuvre. This is consid

ered a positive test when this provocative manoeuvre elicits pain in the medial elbow, indicating ulnar collateral ligament injury. Injury seen among repetitive throwing athletes Onset can be acute (‘pop’) or insidious with medial elbow pain, tightness and decreased throwing velocity Dynamic ultrasound or MRI can be used to characterise the location of the UCL pathology First-line treatment is conservative management with cessation of throwing followed by structured rehabilitation Surgical options include UCL reconstruction (gold standard) or ligament repair with an internal brace

Hip Femoroacetabular impingement and dysplasia Background Intra-articular hip derangements most commonly manifest as anterolateral groin pain in a characteristic distribution, referred to as a ‘C-sign’ ( Figure 36.4 ). In a young patient, two common sources of groin pain with intra-articular origin are femoroacetabular impingement (FAI) and dysplasia. These conditions are considered in some detail in Chapter 39 are described here as they can present as a sports-related injury . History and physical examination Y oung patients with a history of groin pain or repetitive ‘groin or hip flexor sprains’ should be evaluated for dysplasia or FAI. Physical examination focuses on hip range of motion, strength, palpation and provocative manoeuvres. Some important manoeuvres include the FADIR examination, which stands for hip Flexion, ADduction and Internal Rotation, which is specific for impingement pathologies, but the FABER (Flex ion, ABduction and External Rotation) manoeuvre as well as resisted hip flexion (Stinchfield testing) can also identify true 7 intra-articular pathologies. Imaging Initial imaging includes radiographs of the pelvis and the a ff ected hip. Anteroposterior pelvis and false profile views can help determine lateral or anterior coverage of the acetabulum, respectively , while 45° Dunn lateral radiographs of the hip are the optimal projection for detecting the presence of a cam lesion ( Figure 36.5 ). Three-dimensional imaging, including CT and MRI, is helpful for better defining the bony morphology and soft-tissue (i.e. labral) integrity , respectively . Frank E Stinchfield , 1910–1992, American orthopaedic surgeon and founder of The Hip Society . Denis M Dunn , 1916–2001, British orthopaedic surgeon. Treatment Once the correct diagnosis is determined both pathologies can initially be treated conservatively using anti-inflammatory drugs, physical therapy and at times intra-articular injection, for example corticosteroid. Should these modalities fail, both FAI and dysplasia have their own specific surgical interven - tions: arthroscopy ( Figure 36.6 ) and osteotomy , respectively (see Chapter 39 ). Importantly , the aforementioned interven - tions are only a consideration prior to the development of joint space narrowing and osteoarthritis in an e ff ort to preserve the but 7 hip joint. Differential diagnosis /uni25CF Adductor strain. /uni25CF Hip osteoarthritis. /uni25CF Athletic pubalgia. /uni25CF Lumbar radiculopathy . Summary box 36.3 - Femoroacetabular impingement and dysplasia /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF

Figure 36.4 Example of the C-sign for intra-articular hip pathology when asking a patient to demonstrate where they feel their pain. Preserved Large cam lesion joint space Figure 36.5 Anteroposterior right hip radiograph demonstrating a large cam lesion in the setting of the preserved hip joint space. Intra-articular hip derangements can manifest with anterolateral groin pain in a characteristic distribution (‘C-sign’) Consider pathologies in young patients with a history of groin pain or repetitive ‘groin or hip /f_l exor sprains’ Initial imaging includes radiographs of the pelvis and the affected hip Three-dimensional imaging includes CT (bony morphology) and MRI (soft-tissue integrity) Conservative treatment involves using anti-in /f_l ammatory drugs, physical therapy and/or intra-articular injection Surgical interventions are arthroscopy (FAI) and osteotomy (dysplasia) prior to the development of joint space narrowing and osteoarthritis

Knee anterior cruciate ligament rupture with meniscus tear Background Acute knee injuries are extremely common in most sports that require jumping, twisting and contact. Sports with physical impact or tackling, such as rugby or American football, can result in contact knee injuries that often lead to varus or valgus stresses to the knee, resulting in collateral ligament injuries (i.e. lateral collateral ligament or medial collateral ligament) in addition to concomitant cruciate ligament, meniscus or articular cartilage injuries. More frequently , however, acute non-contact injuries of the knee lead to injury to the anterior cruciate ligament (ACL). The most common mechanism of these injuries is a deceleration when the knee falls into valgus and the tibia externally rotates, leading to a subluxation of the knee. These injuries are often associated with either medial or lateral meniscus injuries. History and physical examination Patients with an acute ACL injury will often report hearing or feeling a pop in their knee followed by a notable e ff usion and/ or haemarthrosis. Once the e ff usion resolves, they may report a paucity of knee pain, often leading the patient to believe that the injury has healed itself. However, patients usually present to a physician after attempting subsequent cutting and pivoting activities, which can lead to recurrent instability . Given that the ACL’s primary function is to restrict anterior translation of the tibia on the femur, the most commonly utilised tests to evaluate the competency of the ACL are the anterior drawer and Lachman tests (see Chapter 35 ). Imaging The initial evaluation of an acute knee injury with e ff usion and/or haemarthrosis necessitates radiographic evaluation. John W Lachman , 1919–2007, Professor and Chairman of the Orthopedic Department at Temple University in Philadelphia, PA, USA. Paul Ferdinand Segond , 1851–1912, French surgeon who was a founder of obstetrics and also an expert of the knee, Paris, France. AP , lateral and merchant views are the minimum recom - mended. These radiographs can be useful for identifying any concomitant injuries, including fractures. A Segond fracture located on the anterolateral tibia is pathognomonic for an ACL injury . If an ACL injury is suspected by physical e xamination, an MRI is performed to better evaluate the intra-articular structures and to aid in surgical planning. A systematic eval - uation of the MRI is necessary to ensure that no additional pathology is missed ( Figure 36.7 ). ‘Kissing lesions’ of bony oedema seen on fluid-sensitive sequences on the posterolateral tibia and la teral femoral condyle are also pathognomonic for ACL rupture and represent the pivot shift knee subluxation seen in the setting of ACL rupture. Treatment ACL injuries can be managed conservatively through activ - ity modification and bracing. Should these modalities fail, surgery is an excellent option for restoration of knee stability and to decrease the potential for further meniscal or articular cartilage degeneration. ACL repair has recently become a resurging option for proximal-type tears when the ACL can be restored back to its anatomic footprint on the femur. The bridge-enhanced ACL repair (BEAR) technique using a colla - gen sca ff old is currently under clinical trial and may emerge as an option in the future. The gold standard for ACL, however, is reconstruction. In younger pa tients, large multicentre cohort studies have indicated that autograft reconstruction o ff ers the best durability and lowest chance for re-rupture. Options for autograft reconstruction include bone–patellar tendon–bone, hamstring and quadriceps–tendon autografts. For older and

Femoral osteoplasty Labral repair Burr Figure 36.6 Hip arthroscopic image viewed through the mid-anterior portal with a 70° arthroscope. Complete ACL rupture Figure 36.7 Sagittal proton density magnetic resonance image of the knee demonstrating a complete proximal anterior cruciate ligament (ACL) rupture.

tendon reconstruction provides an additional graft option. Meniscal tears are frequently encountered in the setting 8 of ACL rupture. Common tear patterns encountered include radial tears, root tears and bucket-handle tears where the torn portion of the meniscus can flip like a bucket handle into the centre of the joint. Previously , meniscus tears were treated with partial excision to remove any mechanical disruptions and associated pain, but in recent years the joint preservation func tions of the menisci as well as their contribution to stability of the knee have been better appreciated, leading to e ff orts to pre serve as much meniscal tissue as possible, especially in younger patients. Various methods of meniscus repair ar e currently utilised to restore the meniscus anatomy , including all-inside devices, inside-out, outside-in and root re pair techniques, the details of which are beyond the scope of this chapter. Biolog ical strategies, to augment the repair, are being evaluated in some centres. Differential diagnosis /uni25CF Patellar dislocation. /uni25CF Posterior cruciate ligament rupture. /uni25CF Medial collateral ligament knee rupture. /uni25CF Posterolateral corner knee ligament injury . /uni25CF Patellar tendon rupture. Summary box 36.4 ACL ruptures /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF

Mechanism is commonly a non-contact pivoting injury or a direct impact to the lateral knee Patients often hear or feel a pop in their knee followed by a notable effusion and may experience instability when returning to cutting and pivoting activities Radiographic evaluation includes AP , lateral and merchant views MRI is performed to better evaluate the intra-articular structures, aid in surgical planning and ensure that no additional pathology is missed ACL injuries can be managed conservatively through activity modi /f_i cation and bracing Surgical options include ACL reconstruction (gold standard) and repair in certain select scenarios

COMMONL Y ENCOUNTERED REGIONAL INJURIES Shoulder

Shoulder instability and rotator cuff tear Background Shoulder injuries a ff ect athletes of all ages; however, the distribution of shoulder injuries varies between young and Rudolph Grashey , 1876–1950, Professor of Roentgenology , University of Cologne, Cologne, Germany . Alfred-Armand-Louis-Marie Velpeau , 1795–1867, French anatomist and surgeon. Harold Arthur Hill , 1901–1973, radiologist, San Francisco, CA, USA. Maurice David Sachs , 1909–1987, radiologist, San Francisco, CA, USA. older participants. In athletes younger than 30 years old, espe - cially those participating in contact sports, anterior shoulder dislocations can occur in instances of traumatic or forced shoulder abduction and external rotation. Unfortunately , such dislocations, even if r educed, lead to some degree of stretch - ing of the anterior capsule and tearing of the anteroinferior labrum, which places the patient at risk for further instability events. In older patients who experience falls and sustain the same anterior shoulder dislocations, additional pathologies, including rotator cu ff tears , can occur. History and physical examination Patients who sustain a shoulder dislocation often describe a violent injury event such as a fall or tackle with the arm in some degree of abduction. Patients will often describe a sensation of their shoulder feeling out of place, especially if - the shoulder does not spontaneously reduce. An important component of the history involves the details of the disloca - tion(s): self-reduction versus emergency department reduction, length of time dislocated prior to reduction, prior dislocations, extremity numbness, general ligamentous laxity and activity profile – all of these details have implications for management. Examination in the acute period should focus on e valuating anterior apprehension or subjective patient discomfort and fear of re-dislocation in the positions of abduction and exter - nal rotation of the shoulder, as well as rotator cu ff strength and neurovascular integrity , especially of the axillary nerve (see 1,2 Further reading ). Imaging Radiographs, including at least true anteroposterior (AP) or Grashey , scapular Y , axillary or V elpeau views, should be obtained in all circumstances and evaluated to confirm glenohumeral reduction while ruling out associated fractures, such as Hill–Sachs deformities or glenoid rim fractures.

To assess the patient and offer treatment and • rehabilitation plans

Specific views, including the West Point axillary and the Stryker notch views, can be helpful for evaluating glenoid rim or Bankart fractures or Hill–Sachs lesions, respectively . In cases of recurrent instability where glenoid bone loss is suspected, computed tomography (CT) with or without three-dimensional reconstruction can be helpful in further determining the extent of bone loss. In most instances of anterior instability , magnetic resonance imaging (MRI) is recommended ( Figure 36.1 evaluate for concomitant soft-tissue injuries, including rotator cu ff tears, humeral avulsions of the glenohumeral ligament (HAGL), glenolabral articular disruptions (GLAD) or anterior labrum periosteal sleeve avulsion (ALPSA). Treatment After reduction of an acute anterior glenohumeral dislocation, patients are typically placed in a sling for the first few days. important to begin early gentle range of motion of the shoul der through pendulum exercises but also to continue to move the elbow , wrist and digits actively to maintain range of motion in those distal joints. The initial period is then progressed to increased passive and then active and active-assisted range of motion of the shoulder. Once range of motion has returned to near normal, rotator cu ff and scapular strengthening is progressed. Surgery is considered for even first-time dislo cators based upon stratification of several factors, including younger age, activity profile and pathology present on imag ing. Furthermore, depending upon the pathology present, the surgical options exist on a continuum fr om arthroscopic capsulolabral repair to open capsulolabral repair and capsular 3,4 shift to glenoid bony augmentation procedur es. Regardless of the treatment method chosen, athletes are cleared to return William Schamel Stryker , 1916–2015, orthopedic surgeon and Captain in the United States Navy . Arthur Sydney Blundell Bankart , 1879–1951, orthopaedic surgeon, The Middlesex Hospital, London, UK. to normal levels. Older athletes who acutely tear their rotator cu ff in the set - ting of shoulder dislocations can be considered for acute rota - 5 tor cu ff repair. The treatment of rotator cu ff tears has evolved over several years and current techniques of arthroscopic repair with a knotless, linked, double-row construct ( Figure 36.2 ) have demonstrated excellent patient-reported outcomes with low re-tear rates. Differential diagnosis /uni25CF Proximal humerus fracture. /uni25CF Greater tuberosity fracture. /uni25CF Acromioclavicular joint separation. Summary box 36.1 Shoulder instability /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF ) to 2 It is - - -

Anterior labral tear Figure 36.1 Axial /f_l uid-sensitive magnetic resonance image of the shoulder demonstrating an anterior labral tear. Dislocations occur in instances of traumatic or forced shoulder abduction and external rotation Details of the reduction, time dislocated, history of prior dislocations, general ligamentous laxity and activity pro /f_i le have implications for management Radiographs to con /f_i rm glenohumeral reduction include true AP or Grashey, scapular Y , axillary or Velpeau views A sling should be used for a few days following an acute anterior glenohumeral dislocation Surgery is considered based upon strati /f_i cation of several factors, including younger age, activity pro /f_i le and pathology present on imaging Rotator cuff tendon Suture anchor with repair sutures Figure 36.2 Shoulder arthroscopic image of a rotator cuff repair viewed from the subacromial space through a lateral portal with a 30° arthroscope.

Ulnar collateral ligament tear Background The anterior band of the ulnar collateral ligament (UCL) is the primary stabiliser to valgus stress at the elbow . Anatomi cally this ligament courses from the medial epicondyle of the humerus to the sublime tubercle of the ulna. Although it can be injured acutely through mechanisms of elbow dislocations, pathology is most frequently encountered in repetitive thro ing athletes, such as baseball pitchers and javelin throwers. In the late cocking and early acceleration phases of throwing the ligament is under its maximum stress and at this stage is at the highest risk of ruptur e and chronic attenuation. History and physical examination Throwers who sustain ruptures of their UCL commonly pres ent with two sets of complaints. Rarely , the thrower will recall an acute episode when they heard a pop in the throwing cycle followed by medial elbow pain and pain worse with throwing. The v ast majority of throwers complain of medial elbow pain and tightness coupled with decreased velocity that comes on more insidiously . Examination focuses on provocative manoeuvres that are specific for the UCL, including valgus stress and the moving valgus stress tests or milking manoeuvre ( Figure 36.3 ), in which the examiner provides a valgus stress 6 through elbow range of motion. Pain at the medial elbow during these manoeuvres is specific for UCL pathology . The examiner should also focus on both ulnar nerve sensory and motor symptoms in the hand in addition to ulnar nerve sublux ation as these pathologies can a ff ect the proposed treatment algorithm. Imaging Radiographs of the elbow include a series of AP , lateral, inter nal and external oblique views. These can help rule out other commonly encountered phenomena seen in overhead throwing athletes, including medial epicondyle fractures, posteromedial impingement and capitellar osteochondral defects. When UCL pathology is suspected, dynamic ultrasound is a helpful imaging modality to help characterise the loca tion of the UCL pathology . Moreover, it permits easy examination of the contralateral elbow , which can help to quantify incongruities in medial elbow joint space gapping, an indirect gauge of tear severity . MRI is commonly obtained to precisely define the location of the UCL tear as well as to better evaluate the articular cartilage and the flexor pronator mass, which can also commonly be a ff ected. Treatment Conservative management of UCL injuries is considered first line treatment and typically entails a period of several months of cessation of throwing followed by structured rehabilitation that includes strengthening of secondary stabilising muscles 6 about the elbow and a g radual return of throwing. The use of biological injections, including platelet-rich plasma, has been To m my Jo h n s u rge r y , named after Thomas Edward John Jr, the first major league baseball pitcher who received an ulnar collateral ligament reconstruction in 1974. - w - - proposed for partial-thickness ligament tears in some centres, but more clinical evidence is required. Although ligament repair with an internal brace has recently been demonstrated to have e ffi cacy in certain types of tears, the gold standard for surgical treatment is UCL reconstruction or Tommy John surgery . The surgery involves an autograft tendon harvest, commonly utilising the ipsilateral palmaris longus tendon, and reconstruction of the ligament through bone tunnels in - 6 both the humerus and ulna. This surgery can be coupled with in situ decompression or transposition of the ulnar nerve, if indicated. Ulnar reconstruction surgery is indicated for the highest level of throwers who wish to continue playing their respective sport, with return to sport taking anywhere from - 12 /uni00A0 to 18 months. Differential diagnosis /uni25CF Flexor pronator mass sprain. /uni25CF Ulnohumeral arthritis. /uni25CF Ulnar nerve compression or subluxation. /uni25CF Loose body . Summary box 36.2 UCL tears /uni25CF /uni25CF /uni25CF - /uni25CF /uni25CF

Examiner stabilises patient’s elbow Examiner pulls patient’s thumb with downward force Figure 36.3 Demonstration of the milking manoeuvre. This is consid

ered a positive test when this provocative manoeuvre elicits pain in the medial elbow, indicating ulnar collateral ligament injury. Injury seen among repetitive throwing athletes Onset can be acute (‘pop’) or insidious with medial elbow pain, tightness and decreased throwing velocity Dynamic ultrasound or MRI can be used to characterise the location of the UCL pathology First-line treatment is conservative management with cessation of throwing followed by structured rehabilitation Surgical options include UCL reconstruction (gold standard) or ligament repair with an internal brace

Hip Femoroacetabular impingement and dysplasia Background Intra-articular hip derangements most commonly manifest as anterolateral groin pain in a characteristic distribution, referred to as a ‘C-sign’ ( Figure 36.4 ). In a young patient, two common sources of groin pain with intra-articular origin are femoroacetabular impingement (FAI) and dysplasia. These conditions are considered in some detail in Chapter 39 are described here as they can present as a sports-related injury . History and physical examination Y oung patients with a history of groin pain or repetitive ‘groin or hip flexor sprains’ should be evaluated for dysplasia or FAI. Physical examination focuses on hip range of motion, strength, palpation and provocative manoeuvres. Some important manoeuvres include the FADIR examination, which stands for hip Flexion, ADduction and Internal Rotation, which is specific for impingement pathologies, but the FABER (Flex ion, ABduction and External Rotation) manoeuvre as well as resisted hip flexion (Stinchfield testing) can also identify true 7 intra-articular pathologies. Imaging Initial imaging includes radiographs of the pelvis and the a ff ected hip. Anteroposterior pelvis and false profile views can help determine lateral or anterior coverage of the acetabulum, respectively , while 45° Dunn lateral radiographs of the hip are the optimal projection for detecting the presence of a cam lesion ( Figure 36.5 ). Three-dimensional imaging, including CT and MRI, is helpful for better defining the bony morphology and soft-tissue (i.e. labral) integrity , respectively . Frank E Stinchfield , 1910–1992, American orthopaedic surgeon and founder of The Hip Society . Denis M Dunn , 1916–2001, British orthopaedic surgeon. Treatment Once the correct diagnosis is determined both pathologies can initially be treated conservatively using anti-inflammatory drugs, physical therapy and at times intra-articular injection, for example corticosteroid. Should these modalities fail, both FAI and dysplasia have their own specific surgical interven - tions: arthroscopy ( Figure 36.6 ) and osteotomy , respectively (see Chapter 39 ). Importantly , the aforementioned interven - tions are only a consideration prior to the development of joint space narrowing and osteoarthritis in an e ff ort to preserve the but 7 hip joint. Differential diagnosis /uni25CF Adductor strain. /uni25CF Hip osteoarthritis. /uni25CF Athletic pubalgia. /uni25CF Lumbar radiculopathy . Summary box 36.3 - Femoroacetabular impingement and dysplasia /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF

Figure 36.4 Example of the C-sign for intra-articular hip pathology when asking a patient to demonstrate where they feel their pain. Preserved Large cam lesion joint space Figure 36.5 Anteroposterior right hip radiograph demonstrating a large cam lesion in the setting of the preserved hip joint space. Intra-articular hip derangements can manifest with anterolateral groin pain in a characteristic distribution (‘C-sign’) Consider pathologies in young patients with a history of groin pain or repetitive ‘groin or hip /f_l exor sprains’ Initial imaging includes radiographs of the pelvis and the affected hip Three-dimensional imaging includes CT (bony morphology) and MRI (soft-tissue integrity) Conservative treatment involves using anti-in /f_l ammatory drugs, physical therapy and/or intra-articular injection Surgical interventions are arthroscopy (FAI) and osteotomy (dysplasia) prior to the development of joint space narrowing and osteoarthritis

Knee anterior cruciate ligament rupture with meniscus tear Background Acute knee injuries are extremely common in most sports that require jumping, twisting and contact. Sports with physical impact or tackling, such as rugby or American football, can result in contact knee injuries that often lead to varus or valgus stresses to the knee, resulting in collateral ligament injuries (i.e. lateral collateral ligament or medial collateral ligament) in addition to concomitant cruciate ligament, meniscus or articular cartilage injuries. More frequently , however, acute non-contact injuries of the knee lead to injury to the anterior cruciate ligament (ACL). The most common mechanism of these injuries is a deceleration when the knee falls into valgus and the tibia externally rotates, leading to a subluxation of the knee. These injuries are often associated with either medial or lateral meniscus injuries. History and physical examination Patients with an acute ACL injury will often report hearing or feeling a pop in their knee followed by a notable e ff usion and/ or haemarthrosis. Once the e ff usion resolves, they may report a paucity of knee pain, often leading the patient to believe that the injury has healed itself. However, patients usually present to a physician after attempting subsequent cutting and pivoting activities, which can lead to recurrent instability . Given that the ACL’s primary function is to restrict anterior translation of the tibia on the femur, the most commonly utilised tests to evaluate the competency of the ACL are the anterior drawer and Lachman tests (see Chapter 35 ). Imaging The initial evaluation of an acute knee injury with e ff usion and/or haemarthrosis necessitates radiographic evaluation. John W Lachman , 1919–2007, Professor and Chairman of the Orthopedic Department at Temple University in Philadelphia, PA, USA. Paul Ferdinand Segond , 1851–1912, French surgeon who was a founder of obstetrics and also an expert of the knee, Paris, France. AP , lateral and merchant views are the minimum recom - mended. These radiographs can be useful for identifying any concomitant injuries, including fractures. A Segond fracture located on the anterolateral tibia is pathognomonic for an ACL injury . If an ACL injury is suspected by physical e xamination, an MRI is performed to better evaluate the intra-articular structures and to aid in surgical planning. A systematic eval - uation of the MRI is necessary to ensure that no additional pathology is missed ( Figure 36.7 ). ‘Kissing lesions’ of bony oedema seen on fluid-sensitive sequences on the posterolateral tibia and la teral femoral condyle are also pathognomonic for ACL rupture and represent the pivot shift knee subluxation seen in the setting of ACL rupture. Treatment ACL injuries can be managed conservatively through activ - ity modification and bracing. Should these modalities fail, surgery is an excellent option for restoration of knee stability and to decrease the potential for further meniscal or articular cartilage degeneration. ACL repair has recently become a resurging option for proximal-type tears when the ACL can be restored back to its anatomic footprint on the femur. The bridge-enhanced ACL repair (BEAR) technique using a colla - gen sca ff old is currently under clinical trial and may emerge as an option in the future. The gold standard for ACL, however, is reconstruction. In younger pa tients, large multicentre cohort studies have indicated that autograft reconstruction o ff ers the best durability and lowest chance for re-rupture. Options for autograft reconstruction include bone–patellar tendon–bone, hamstring and quadriceps–tendon autografts. For older and

Femoral osteoplasty Labral repair Burr Figure 36.6 Hip arthroscopic image viewed through the mid-anterior portal with a 70° arthroscope. Complete ACL rupture Figure 36.7 Sagittal proton density magnetic resonance image of the knee demonstrating a complete proximal anterior cruciate ligament (ACL) rupture.

tendon reconstruction provides an additional graft option. Meniscal tears are frequently encountered in the setting 8 of ACL rupture. Common tear patterns encountered include radial tears, root tears and bucket-handle tears where the torn portion of the meniscus can flip like a bucket handle into the centre of the joint. Previously , meniscus tears were treated with partial excision to remove any mechanical disruptions and associated pain, but in recent years the joint preservation func tions of the menisci as well as their contribution to stability of the knee have been better appreciated, leading to e ff orts to pre serve as much meniscal tissue as possible, especially in younger patients. Various methods of meniscus repair ar e currently utilised to restore the meniscus anatomy , including all-inside devices, inside-out, outside-in and root re pair techniques, the details of which are beyond the scope of this chapter. Biolog ical strategies, to augment the repair, are being evaluated in some centres. Differential diagnosis /uni25CF Patellar dislocation. /uni25CF Posterior cruciate ligament rupture. /uni25CF Medial collateral ligament knee rupture. /uni25CF Posterolateral corner knee ligament injury . /uni25CF Patellar tendon rupture. Summary box 36.4 ACL ruptures /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF

Mechanism is commonly a non-contact pivoting injury or a direct impact to the lateral knee Patients often hear or feel a pop in their knee followed by a notable effusion and may experience instability when returning to cutting and pivoting activities Radiographic evaluation includes AP , lateral and merchant views MRI is performed to better evaluate the intra-articular structures, aid in surgical planning and ensure that no additional pathology is missed ACL injuries can be managed conservatively through activity modi /f_i cation and bracing Surgical options include ACL reconstruction (gold standard) and repair in certain select scenarios

COMMONL Y ENCOUNTERED REGIONAL INJURIES Shoulder

Shoulder instability and rotator cuff tear Background Shoulder injuries a ff ect athletes of all ages; however, the distribution of shoulder injuries varies between young and Rudolph Grashey , 1876–1950, Professor of Roentgenology , University of Cologne, Cologne, Germany . Alfred-Armand-Louis-Marie Velpeau , 1795–1867, French anatomist and surgeon. Harold Arthur Hill , 1901–1973, radiologist, San Francisco, CA, USA. Maurice David Sachs , 1909–1987, radiologist, San Francisco, CA, USA. older participants. In athletes younger than 30 years old, espe - cially those participating in contact sports, anterior shoulder dislocations can occur in instances of traumatic or forced shoulder abduction and external rotation. Unfortunately , such dislocations, even if r educed, lead to some degree of stretch - ing of the anterior capsule and tearing of the anteroinferior labrum, which places the patient at risk for further instability events. In older patients who experience falls and sustain the same anterior shoulder dislocations, additional pathologies, including rotator cu ff tears , can occur. History and physical examination Patients who sustain a shoulder dislocation often describe a violent injury event such as a fall or tackle with the arm in some degree of abduction. Patients will often describe a sensation of their shoulder feeling out of place, especially if - the shoulder does not spontaneously reduce. An important component of the history involves the details of the disloca - tion(s): self-reduction versus emergency department reduction, length of time dislocated prior to reduction, prior dislocations, extremity numbness, general ligamentous laxity and activity profile – all of these details have implications for management. Examination in the acute period should focus on e valuating anterior apprehension or subjective patient discomfort and fear of re-dislocation in the positions of abduction and exter - nal rotation of the shoulder, as well as rotator cu ff strength and neurovascular integrity , especially of the axillary nerve (see 1,2 Further reading ). Imaging Radiographs, including at least true anteroposterior (AP) or Grashey , scapular Y , axillary or V elpeau views, should be obtained in all circumstances and evaluated to confirm glenohumeral reduction while ruling out associated fractures, such as Hill–Sachs deformities or glenoid rim fractures.

To assess the patient and offer treatment and • rehabilitation plans

Specific views, including the West Point axillary and the Stryker notch views, can be helpful for evaluating glenoid rim or Bankart fractures or Hill–Sachs lesions, respectively . In cases of recurrent instability where glenoid bone loss is suspected, computed tomography (CT) with or without three-dimensional reconstruction can be helpful in further determining the extent of bone loss. In most instances of anterior instability , magnetic resonance imaging (MRI) is recommended ( Figure 36.1 evaluate for concomitant soft-tissue injuries, including rotator cu ff tears, humeral avulsions of the glenohumeral ligament (HAGL), glenolabral articular disruptions (GLAD) or anterior labrum periosteal sleeve avulsion (ALPSA). Treatment After reduction of an acute anterior glenohumeral dislocation, patients are typically placed in a sling for the first few days. important to begin early gentle range of motion of the shoul der through pendulum exercises but also to continue to move the elbow , wrist and digits actively to maintain range of motion in those distal joints. The initial period is then progressed to increased passive and then active and active-assisted range of motion of the shoulder. Once range of motion has returned to near normal, rotator cu ff and scapular strengthening is progressed. Surgery is considered for even first-time dislo cators based upon stratification of several factors, including younger age, activity profile and pathology present on imag ing. Furthermore, depending upon the pathology present, the surgical options exist on a continuum fr om arthroscopic capsulolabral repair to open capsulolabral repair and capsular 3,4 shift to glenoid bony augmentation procedur es. Regardless of the treatment method chosen, athletes are cleared to return William Schamel Stryker , 1916–2015, orthopedic surgeon and Captain in the United States Navy . Arthur Sydney Blundell Bankart , 1879–1951, orthopaedic surgeon, The Middlesex Hospital, London, UK. to normal levels. Older athletes who acutely tear their rotator cu ff in the set - ting of shoulder dislocations can be considered for acute rota - 5 tor cu ff repair. The treatment of rotator cu ff tears has evolved over several years and current techniques of arthroscopic repair with a knotless, linked, double-row construct ( Figure 36.2 ) have demonstrated excellent patient-reported outcomes with low re-tear rates. Differential diagnosis /uni25CF Proximal humerus fracture. /uni25CF Greater tuberosity fracture. /uni25CF Acromioclavicular joint separation. Summary box 36.1 Shoulder instability /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF ) to 2 It is - - -

Anterior labral tear Figure 36.1 Axial /f_l uid-sensitive magnetic resonance image of the shoulder demonstrating an anterior labral tear. Dislocations occur in instances of traumatic or forced shoulder abduction and external rotation Details of the reduction, time dislocated, history of prior dislocations, general ligamentous laxity and activity pro /f_i le have implications for management Radiographs to con /f_i rm glenohumeral reduction include true AP or Grashey, scapular Y , axillary or Velpeau views A sling should be used for a few days following an acute anterior glenohumeral dislocation Surgery is considered based upon strati /f_i cation of several factors, including younger age, activity pro /f_i le and pathology present on imaging Rotator cuff tendon Suture anchor with repair sutures Figure 36.2 Shoulder arthroscopic image of a rotator cuff repair viewed from the subacromial space through a lateral portal with a 30° arthroscope.

Ulnar collateral ligament tear Background The anterior band of the ulnar collateral ligament (UCL) is the primary stabiliser to valgus stress at the elbow . Anatomi cally this ligament courses from the medial epicondyle of the humerus to the sublime tubercle of the ulna. Although it can be injured acutely through mechanisms of elbow dislocations, pathology is most frequently encountered in repetitive thro ing athletes, such as baseball pitchers and javelin throwers. In the late cocking and early acceleration phases of throwing the ligament is under its maximum stress and at this stage is at the highest risk of ruptur e and chronic attenuation. History and physical examination Throwers who sustain ruptures of their UCL commonly pres ent with two sets of complaints. Rarely , the thrower will recall an acute episode when they heard a pop in the throwing cycle followed by medial elbow pain and pain worse with throwing. The v ast majority of throwers complain of medial elbow pain and tightness coupled with decreased velocity that comes on more insidiously . Examination focuses on provocative manoeuvres that are specific for the UCL, including valgus stress and the moving valgus stress tests or milking manoeuvre ( Figure 36.3 ), in which the examiner provides a valgus stress 6 through elbow range of motion. Pain at the medial elbow during these manoeuvres is specific for UCL pathology . The examiner should also focus on both ulnar nerve sensory and motor symptoms in the hand in addition to ulnar nerve sublux ation as these pathologies can a ff ect the proposed treatment algorithm. Imaging Radiographs of the elbow include a series of AP , lateral, inter nal and external oblique views. These can help rule out other commonly encountered phenomena seen in overhead throwing athletes, including medial epicondyle fractures, posteromedial impingement and capitellar osteochondral defects. When UCL pathology is suspected, dynamic ultrasound is a helpful imaging modality to help characterise the loca tion of the UCL pathology . Moreover, it permits easy examination of the contralateral elbow , which can help to quantify incongruities in medial elbow joint space gapping, an indirect gauge of tear severity . MRI is commonly obtained to precisely define the location of the UCL tear as well as to better evaluate the articular cartilage and the flexor pronator mass, which can also commonly be a ff ected. Treatment Conservative management of UCL injuries is considered first line treatment and typically entails a period of several months of cessation of throwing followed by structured rehabilitation that includes strengthening of secondary stabilising muscles 6 about the elbow and a g radual return of throwing. The use of biological injections, including platelet-rich plasma, has been To m my Jo h n s u rge r y , named after Thomas Edward John Jr, the first major league baseball pitcher who received an ulnar collateral ligament reconstruction in 1974. - w - - proposed for partial-thickness ligament tears in some centres, but more clinical evidence is required. Although ligament repair with an internal brace has recently been demonstrated to have e ffi cacy in certain types of tears, the gold standard for surgical treatment is UCL reconstruction or Tommy John surgery . The surgery involves an autograft tendon harvest, commonly utilising the ipsilateral palmaris longus tendon, and reconstruction of the ligament through bone tunnels in - 6 both the humerus and ulna. This surgery can be coupled with in situ decompression or transposition of the ulnar nerve, if indicated. Ulnar reconstruction surgery is indicated for the highest level of throwers who wish to continue playing their respective sport, with return to sport taking anywhere from - 12 /uni00A0 to 18 months. Differential diagnosis /uni25CF Flexor pronator mass sprain. /uni25CF Ulnohumeral arthritis. /uni25CF Ulnar nerve compression or subluxation. /uni25CF Loose body . Summary box 36.2 UCL tears /uni25CF /uni25CF /uni25CF - /uni25CF /uni25CF

Examiner stabilises patient’s elbow Examiner pulls patient’s thumb with downward force Figure 36.3 Demonstration of the milking manoeuvre. This is consid

ered a positive test when this provocative manoeuvre elicits pain in the medial elbow, indicating ulnar collateral ligament injury. Injury seen among repetitive throwing athletes Onset can be acute (‘pop’) or insidious with medial elbow pain, tightness and decreased throwing velocity Dynamic ultrasound or MRI can be used to characterise the location of the UCL pathology First-line treatment is conservative management with cessation of throwing followed by structured rehabilitation Surgical options include UCL reconstruction (gold standard) or ligament repair with an internal brace

Hip Femoroacetabular impingement and dysplasia Background Intra-articular hip derangements most commonly manifest as anterolateral groin pain in a characteristic distribution, referred to as a ‘C-sign’ ( Figure 36.4 ). In a young patient, two common sources of groin pain with intra-articular origin are femoroacetabular impingement (FAI) and dysplasia. These conditions are considered in some detail in Chapter 39 are described here as they can present as a sports-related injury . History and physical examination Y oung patients with a history of groin pain or repetitive ‘groin or hip flexor sprains’ should be evaluated for dysplasia or FAI. Physical examination focuses on hip range of motion, strength, palpation and provocative manoeuvres. Some important manoeuvres include the FADIR examination, which stands for hip Flexion, ADduction and Internal Rotation, which is specific for impingement pathologies, but the FABER (Flex ion, ABduction and External Rotation) manoeuvre as well as resisted hip flexion (Stinchfield testing) can also identify true 7 intra-articular pathologies. Imaging Initial imaging includes radiographs of the pelvis and the a ff ected hip. Anteroposterior pelvis and false profile views can help determine lateral or anterior coverage of the acetabulum, respectively , while 45° Dunn lateral radiographs of the hip are the optimal projection for detecting the presence of a cam lesion ( Figure 36.5 ). Three-dimensional imaging, including CT and MRI, is helpful for better defining the bony morphology and soft-tissue (i.e. labral) integrity , respectively . Frank E Stinchfield , 1910–1992, American orthopaedic surgeon and founder of The Hip Society . Denis M Dunn , 1916–2001, British orthopaedic surgeon. Treatment Once the correct diagnosis is determined both pathologies can initially be treated conservatively using anti-inflammatory drugs, physical therapy and at times intra-articular injection, for example corticosteroid. Should these modalities fail, both FAI and dysplasia have their own specific surgical interven - tions: arthroscopy ( Figure 36.6 ) and osteotomy , respectively (see Chapter 39 ). Importantly , the aforementioned interven - tions are only a consideration prior to the development of joint space narrowing and osteoarthritis in an e ff ort to preserve the but 7 hip joint. Differential diagnosis /uni25CF Adductor strain. /uni25CF Hip osteoarthritis. /uni25CF Athletic pubalgia. /uni25CF Lumbar radiculopathy . Summary box 36.3 - Femoroacetabular impingement and dysplasia /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF

Figure 36.4 Example of the C-sign for intra-articular hip pathology when asking a patient to demonstrate where they feel their pain. Preserved Large cam lesion joint space Figure 36.5 Anteroposterior right hip radiograph demonstrating a large cam lesion in the setting of the preserved hip joint space. Intra-articular hip derangements can manifest with anterolateral groin pain in a characteristic distribution (‘C-sign’) Consider pathologies in young patients with a history of groin pain or repetitive ‘groin or hip /f_l exor sprains’ Initial imaging includes radiographs of the pelvis and the affected hip Three-dimensional imaging includes CT (bony morphology) and MRI (soft-tissue integrity) Conservative treatment involves using anti-in /f_l ammatory drugs, physical therapy and/or intra-articular injection Surgical interventions are arthroscopy (FAI) and osteotomy (dysplasia) prior to the development of joint space narrowing and osteoarthritis

Knee anterior cruciate ligament rupture with meniscus tear Background Acute knee injuries are extremely common in most sports that require jumping, twisting and contact. Sports with physical impact or tackling, such as rugby or American football, can result in contact knee injuries that often lead to varus or valgus stresses to the knee, resulting in collateral ligament injuries (i.e. lateral collateral ligament or medial collateral ligament) in addition to concomitant cruciate ligament, meniscus or articular cartilage injuries. More frequently , however, acute non-contact injuries of the knee lead to injury to the anterior cruciate ligament (ACL). The most common mechanism of these injuries is a deceleration when the knee falls into valgus and the tibia externally rotates, leading to a subluxation of the knee. These injuries are often associated with either medial or lateral meniscus injuries. History and physical examination Patients with an acute ACL injury will often report hearing or feeling a pop in their knee followed by a notable e ff usion and/ or haemarthrosis. Once the e ff usion resolves, they may report a paucity of knee pain, often leading the patient to believe that the injury has healed itself. However, patients usually present to a physician after attempting subsequent cutting and pivoting activities, which can lead to recurrent instability . Given that the ACL’s primary function is to restrict anterior translation of the tibia on the femur, the most commonly utilised tests to evaluate the competency of the ACL are the anterior drawer and Lachman tests (see Chapter 35 ). Imaging The initial evaluation of an acute knee injury with e ff usion and/or haemarthrosis necessitates radiographic evaluation. John W Lachman , 1919–2007, Professor and Chairman of the Orthopedic Department at Temple University in Philadelphia, PA, USA. Paul Ferdinand Segond , 1851–1912, French surgeon who was a founder of obstetrics and also an expert of the knee, Paris, France. AP , lateral and merchant views are the minimum recom - mended. These radiographs can be useful for identifying any concomitant injuries, including fractures. A Segond fracture located on the anterolateral tibia is pathognomonic for an ACL injury . If an ACL injury is suspected by physical e xamination, an MRI is performed to better evaluate the intra-articular structures and to aid in surgical planning. A systematic eval - uation of the MRI is necessary to ensure that no additional pathology is missed ( Figure 36.7 ). ‘Kissing lesions’ of bony oedema seen on fluid-sensitive sequences on the posterolateral tibia and la teral femoral condyle are also pathognomonic for ACL rupture and represent the pivot shift knee subluxation seen in the setting of ACL rupture. Treatment ACL injuries can be managed conservatively through activ - ity modification and bracing. Should these modalities fail, surgery is an excellent option for restoration of knee stability and to decrease the potential for further meniscal or articular cartilage degeneration. ACL repair has recently become a resurging option for proximal-type tears when the ACL can be restored back to its anatomic footprint on the femur. The bridge-enhanced ACL repair (BEAR) technique using a colla - gen sca ff old is currently under clinical trial and may emerge as an option in the future. The gold standard for ACL, however, is reconstruction. In younger pa tients, large multicentre cohort studies have indicated that autograft reconstruction o ff ers the best durability and lowest chance for re-rupture. Options for autograft reconstruction include bone–patellar tendon–bone, hamstring and quadriceps–tendon autografts. For older and

Femoral osteoplasty Labral repair Burr Figure 36.6 Hip arthroscopic image viewed through the mid-anterior portal with a 70° arthroscope. Complete ACL rupture Figure 36.7 Sagittal proton density magnetic resonance image of the knee demonstrating a complete proximal anterior cruciate ligament (ACL) rupture.

tendon reconstruction provides an additional graft option. Meniscal tears are frequently encountered in the setting 8 of ACL rupture. Common tear patterns encountered include radial tears, root tears and bucket-handle tears where the torn portion of the meniscus can flip like a bucket handle into the centre of the joint. Previously , meniscus tears were treated with partial excision to remove any mechanical disruptions and associated pain, but in recent years the joint preservation func tions of the menisci as well as their contribution to stability of the knee have been better appreciated, leading to e ff orts to pre serve as much meniscal tissue as possible, especially in younger patients. Various methods of meniscus repair ar e currently utilised to restore the meniscus anatomy , including all-inside devices, inside-out, outside-in and root re pair techniques, the details of which are beyond the scope of this chapter. Biolog ical strategies, to augment the repair, are being evaluated in some centres. Differential diagnosis /uni25CF Patellar dislocation. /uni25CF Posterior cruciate ligament rupture. /uni25CF Medial collateral ligament knee rupture. /uni25CF Posterolateral corner knee ligament injury . /uni25CF Patellar tendon rupture. Summary box 36.4 ACL ruptures /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF

Mechanism is commonly a non-contact pivoting injury or a direct impact to the lateral knee Patients often hear or feel a pop in their knee followed by a notable effusion and may experience instability when returning to cutting and pivoting activities Radiographic evaluation includes AP , lateral and merchant views MRI is performed to better evaluate the intra-articular structures, aid in surgical planning and ensure that no additional pathology is missed ACL injuries can be managed conservatively through activity modi /f_i cation and bracing Surgical options include ACL reconstruction (gold standard) and repair in certain select scenarios