Ulnar nerve compression

Ulnar nerve compression

Compression of the ulnar nerve most commonly occurs in the cubital tunnel (behind the medial epicondyle) within the arcade of Struthers. It may become compressed by the medial intermuscular septum as the nerve passes into the posterior compartment of the distal humerus. Distally it may also become compressed as the nerve passes between the heads of the flexor carpi ulnaris ( Figure 38.39 ). History and examination Patients describe tingling/numbness in the little and ring fingers. A positive Tinel’s sign is usually present at the compres - sion site, with wasting and weakness of the intrinsic muscles of the hand ( Figure 38.40 ). Froment’s sign may be positive if there is weakness of the adductor pollicis ( Figure 38.41 ). Nerve conduction studies have an unpredictable diagnostic value in the early stages. Radiographs may confirm medial osteophytes or loose bodies if compression is secondary to arthritis. Jules Froment , 1878–1946, Professor of Clinical Medicine, Lyons, France. Treatment Splints preventing elbow flexion at night may be useful if only night symptoms are a problem for the patient. If symptoms persist, surgery can be performed; options include simple nerve decompression (most cases), partial medial epicondylectomy and/or anterior transposition of the nerve. Transposition is necessary in cases of valgus deformity or if the nerve is unstable after decompression.

Figure 38.35 Radiographs showing loose bodies in the elbow (arrow). Figure 38.36 Loose bodies removed arthroscopically from the patient in Figure 38.35 . Figure 38.37 Olecranon bursitis. Figure 38.38 Large chronic olecranon bursa with dense calci /f_i c deposit. (a) Ulnar nerve MCL FCU muscle belly Fibrous arch of FCU (b) Figure 38.39 (a) Anatomy of the cubital tunnel site for ulnar nerve compression, with (b) a view of arthroscopic ulnar nerve decompres

sion. FCU, /f_l exor carpi ulnaris; MCL, medial collateral ligament.

Summary box 38.10 Other common elbow problems /uni25CF /uni25CF /uni25CF

Figure 38.40 Intrinsic muscle wasting on the left due to ulnar neu ropathy. Loose bodies cause locking and can be removed arthroscopically If the ulnar nerve is compressed, weakness and wasting will be seen in the hands Simple decompression is usually successful

Ulnar nerve compression

Compression of the ulnar nerve most commonly occurs in the cubital tunnel (behind the medial epicondyle) within the arcade of Struthers. It may become compressed by the medial intermuscular septum as the nerve passes into the posterior compartment of the distal humerus. Distally it may also become compressed as the nerve passes between the heads of the flexor carpi ulnaris ( Figure 38.39 ). History and examination Patients describe tingling/numbness in the little and ring fingers. A positive Tinel’s sign is usually present at the compres - sion site, with wasting and weakness of the intrinsic muscles of the hand ( Figure 38.40 ). Froment’s sign may be positive if there is weakness of the adductor pollicis ( Figure 38.41 ). Nerve conduction studies have an unpredictable diagnostic value in the early stages. Radiographs may confirm medial osteophytes or loose bodies if compression is secondary to arthritis. Jules Froment , 1878–1946, Professor of Clinical Medicine, Lyons, France. Treatment Splints preventing elbow flexion at night may be useful if only night symptoms are a problem for the patient. If symptoms persist, surgery can be performed; options include simple nerve decompression (most cases), partial medial epicondylectomy and/or anterior transposition of the nerve. Transposition is necessary in cases of valgus deformity or if the nerve is unstable after decompression.

Figure 38.35 Radiographs showing loose bodies in the elbow (arrow). Figure 38.36 Loose bodies removed arthroscopically from the patient in Figure 38.35 . Figure 38.37 Olecranon bursitis. Figure 38.38 Large chronic olecranon bursa with dense calci /f_i c deposit. (a) Ulnar nerve MCL FCU muscle belly Fibrous arch of FCU (b) Figure 38.39 (a) Anatomy of the cubital tunnel site for ulnar nerve compression, with (b) a view of arthroscopic ulnar nerve decompres

sion. FCU, /f_l exor carpi ulnaris; MCL, medial collateral ligament.

Summary box 38.10 Other common elbow problems /uni25CF /uni25CF /uni25CF

Figure 38.40 Intrinsic muscle wasting on the left due to ulnar neu ropathy. Loose bodies cause locking and can be removed arthroscopically If the ulnar nerve is compressed, weakness and wasting will be seen in the hands Simple decompression is usually successful

Ulnar nerve compression

Compression of the ulnar nerve most commonly occurs in the cubital tunnel (behind the medial epicondyle) within the arcade of Struthers. It may become compressed by the medial intermuscular septum as the nerve passes into the posterior compartment of the distal humerus. Distally it may also become compressed as the nerve passes between the heads of the flexor carpi ulnaris ( Figure 38.39 ). History and examination Patients describe tingling/numbness in the little and ring fingers. A positive Tinel’s sign is usually present at the compres - sion site, with wasting and weakness of the intrinsic muscles of the hand ( Figure 38.40 ). Froment’s sign may be positive if there is weakness of the adductor pollicis ( Figure 38.41 ). Nerve conduction studies have an unpredictable diagnostic value in the early stages. Radiographs may confirm medial osteophytes or loose bodies if compression is secondary to arthritis. Jules Froment , 1878–1946, Professor of Clinical Medicine, Lyons, France. Treatment Splints preventing elbow flexion at night may be useful if only night symptoms are a problem for the patient. If symptoms persist, surgery can be performed; options include simple nerve decompression (most cases), partial medial epicondylectomy and/or anterior transposition of the nerve. Transposition is necessary in cases of valgus deformity or if the nerve is unstable after decompression.

Figure 38.35 Radiographs showing loose bodies in the elbow (arrow). Figure 38.36 Loose bodies removed arthroscopically from the patient in Figure 38.35 . Figure 38.37 Olecranon bursitis. Figure 38.38 Large chronic olecranon bursa with dense calci /f_i c deposit. (a) Ulnar nerve MCL FCU muscle belly Fibrous arch of FCU (b) Figure 38.39 (a) Anatomy of the cubital tunnel site for ulnar nerve compression, with (b) a view of arthroscopic ulnar nerve decompres

sion. FCU, /f_l exor carpi ulnaris; MCL, medial collateral ligament.

Summary box 38.10 Other common elbow problems /uni25CF /uni25CF /uni25CF

Figure 38.40 Intrinsic muscle wasting on the left due to ulnar neu ropathy. Loose bodies cause locking and can be removed arthroscopically If the ulnar nerve is compressed, weakness and wasting will be seen in the hands Simple decompression is usually successful