Anatomical variation of the posterior interosseous nerve: a cadaver dissection study.

An anatomical variation of the posterior interosseous nerve was found in a cadaver. The posterior interosseous nerve entered the supinator muscle 3 cm distal to the radiohumeral joint, but exited from two sites. Fifty percent of the nerve exited under the distal edge of the supinator muscle. The other 50% of the nerve pierced through the supinator muscle, 4.2 cm distal to the articular surface of the radial head and then joined the remaining posterior interosseous nerve as it emerged from the supinator muscle distally. Variations were not found concerning the order and the manner of branches to the muscles. This variation in the posterior interosseous nerve could be an additional compression site for this nerve and therefore responsible for some of the atypical presentations of symptoms and for partial recovery after surgical decompression. Careful surgical dissection is recommended to avoid injury to this branch.

Preventing carpal tunnel syndrome and cumulative trauma disorder: effect of carpal tunnel decompression excercises: an Oklahoma experience.

An Oklahoma meat packing company with 286 production workers experienced a high incidence of cumulative trauma disorder (CTD), specifically carpal tunnel syndrome (CTS). The company learned about the Carpal Tunnel Decompression Exercises (exercise program) through the American Academy of Orthopedic Surgeons' official web page. The Orthopaedic & Reconstructive Center assisted the company with implementation of the exercise program. The company reported their one-year follow up findings to the Governor's Council on Safety Policy (State of Oklahoma). The exercise program was the only ergonomic change the company implemented that year. The company's workers' compensation loss ratio improved from 13.89% to 11.61%. The company reported a net financial gain after comparing injury reduction versus work time lost to exercise. The incidence of Cumulative Trauma Disorder, excluding Carpal Tunnel Syndrome, was reduced 37% and Carpal Tunnel Syndrome was reduced 45.4%. The results of the exercise program were significant enough that the company made the exercise program permanent.

The Oklahoma repair technique: a biomechanical study of a new suture repair technique.

We designed and evaluated the biomechanical advantages of a new (Oklahoma) suture technique for repairing flexor tendons in fresh, frozen cadaver specimens. Forty flexor digitorum profundi tendons from the middle three fingers were sharply cut and repaired with a number 3-0 braided polyester using the new technique and the Modified Kessler technique with and without an epitenon repair. The repaired tendons were then stressed to failure. The Modified Kessler with epitendon repair initiated gap formation on an average of 15.3 +/- 2.7 newtons and failed at 40.9 +/- 4.3 newtons. The Oklahoma suture technique with a running epitenon repair initiated gap formation on average of 48.6 (SD +/- 4.0) newtons and required an average load of 57.9 (SD +/- 3.0) newtons to fail. Thus, it was significantly stronger than the modified Kessler technique with epitendon repair (P < 0.01). The tendons repaired with the Oklahoma and epitenon repair suture technique did not form a 2 mm gap prior to failure. The epitendon repair increased the resistance to gap formation by 80% to 100% and the repair failure by 17.5% to 25% for both types of repairs. We concluded that the addition of the epitendon repair increases the tensile strength of the repair regardless of the core suture technique, and it should be used. In comparison with the Modified Kessler repair technique, the Oklahoma repair technique has superior tolerance to gap initiation, 2 mm gap formation, and physical failure of the repaired tendon.

Anatomic variation of the extensor tendons to the ring and little fingers: a cadaver dissection study.

We found an anatomic variation of the extensor digiti minimi (EDM) and extensor digitorum communis (EDC) in a cadaveric dissection. The EDM had three tendon slips; two slips to the little finger and one to the ring finger metacarpophalangeal (MP) joint. The ring finger slip inserted in the extensor hood with the EDC. The EDC had a separate tendon to the little finger extensor hood. The EDM had an additional pulley distal to the extensor retinaculum. The MP joints of the little and ring fingers extended simultaneously upon pulling the EDM or the EDC. The third slip of the EDM could provide an extra donor site and possibly poses a unique clinical presentation.

Clinical significance of an extensor tendon anomaly to the little finger--a new finding.

A new anatomical variation of extensor digiti minimi (EDM) was discovered during our anatomical studies. The EDM usually gives one tendon to the little finger to extend the metacarpophalangeal joint (MPJ) independently from the other fingers. The EDM in our cadaver had three tendon slips. It supplied the MPJ of the little finger with two tendon slips. Along with the extensor digitorum communis (EDC), the EDM also had an additional slip to the ring finger MPJ extensor hood apparatus. The little finger also received a separate tendon from EDC.

The Posterior Interosseous Nerve Anatomical Variation and Surgical Consideration - A Case Report of Cadaver Study.

We found an anatomical variation of the posterior interosseous nerve (PIN) in a cadaver. The PIN entered the supinator muscle 3 cm distal to the radiohumeral joint, but exited from two sites. 50% of the nerve exited under the distal edge of the supinator muscle. The other half of the nerve pierced through the supinator muscle, 4.2 cm distal to the articular surface of the radial head and then joined the remaining PIN as it emerged from the supinator muscle distally. We did not find variations concerning the order and the manner of branches to the muscles. This variation in the PIN could be an additional compression site for this nerve; and therefore responsible for some of the atypical presentations of symptoms and for partial recovery after surgical decompression. A careful surgical dissection should be recommended to avoid injury to this branch.

Cubital tunnel release with medial epicondylectomy factors influencing the outcome.

From 347 cases of documented cubital tunnel syndrome, 160 required cubital tunnel release and medial epicondylectomy over a 10-year period and were considered for this retrospective study. These patients were monitored for 3 years after surgery. According to the modified scale of McGowan, 86% of patients were considered stage II. Eighty-one percent of the patients were symptom free, and 96% of the patients improved by 1 Wilson and Krout grade following surgery. We considered return of symptoms 3 months or longer after surgery as recurrence; there were 21 recurrences. There was no correlation between recurrence and limb dominance, patient age at the time of surgery, or length of preoperative conservative treatment. Of the patients with recurrences, 44% were in their fourth decade of life. The rate of recurrence in females (18%) was almost twice that in males (10%). The rate of recurrence was increased twofold when the patient did not return to work within 3 months. When concomitant ipsilateral carpal tunnel was present (44%), the recurrence rate was 17% compared with 9% in those without carpal tunnel syndrome. The recurrence rate was 20% when ipsilateral thoracic outlet syndrome was present compared with 9% in patients without other ipsilateral maladies. Therefore, higher recurrence rates should be anticipated in female patients, in patients with concomitant ipsilateral thoracic outlet syndrome and/or carpal tunnel syndrome, in patients in their third or fourth decade of life, or in patients not returning to work within 3 months after surgery.

Cubital tunnel release and medial epicondylectomy: effect of timing of mobilization.

The effects of early versus late range of motion (ROM) following cubital tunnel decompression and medial epicondylectomy were evaluated in a randomized prospective study. Forty-five consecutive procedures were divided into 2 groups. The early mobilization group started rehabilitation at an average of 3 days after surgery and the late mobilization group started rehabilitation at an average of 14 days after surgery. Flexion contracture of more than 5 degrees degrees was observed in 5% of the early mobilization group, compared to 52% of the late mobilization group (p < .001). On average, patients in the early mobilization group returned to work twice as early as those in the late mobilization group and did not experience any adverse effects on their grip strength or other hand functions. Institution of ROM exercises immediately after surgery was found to be more effective in preventing elbow flexion contractures, obtaining a quicker recovery, and allowing return to work with no ill effects.

Treatment of thrombosed thumb artery aneurysm: a report of four cases.

Acute thrombosis of a thumb ulnar digital artery aneurysm is painful and associated with varying degrees of ischemia. Treatment of 4 patients with this condition by resection of thrombosed aneurysm and microsurgical vein graft reconstruction of the involved artery is discussed. Complete relief of symptoms, including healing of ulcerations and reversal of cold intolerance, were achieved. The authors recommend resection of the thrombosed thumb ulnar digital artery aneurysm and re-establishment of arterial flow by an interpositional vein graft.

Free vascularized temporal parietal flap in hand surgery.

Free vascularized temporo-parietal fascia (TPF) flap is a flap of thin, pliable and vascularized tissue which can cover an area measuring up to 12 cm x 14 cm. The flap is harvested based on temporal vessels, which provide a smooth, gliding surface for tendon function and eliminates the need for secondary procedures usually required by the pedicled or bulky free vascularized myocutaneous flaps. The donor pedicle is long and consistent with an average diameter of 3 mm in adults. This flap is versatile. In 12 resurfacings for traumatic wounds of hand and wrist, no flaps were lost. Donor site morbidity, except for a transient sideburn hair loss in one case, was not encountered. We recommend this flap as a viable one-stage procedure for coverage of complex hand wounds.

Early versus late range of motion following cubital tunnel surgery.

The purpose of this study was to evaluate the effects of early versus late range of motion exercises following cubital tunnel release and medial epicondylectomy. Fifty-seven consecutive cases were studied and divided into two groups. Physical therapy consisting of active and passive range of motion exercises was started 14 days postoperatively for the first group and 3 days postoperatively for the second group. Fifty-two percent of the patients in group 1 sustained flexion contractures of more than 5 degrees compared with only 4% of the patients in group 2. Early initiation of therapy did not adversely affect the grip strength and/or other functions of the upper extremity, and the patients in group 2 returned to work sooner than the patients in group 1 (in fact, in half the time). Institution of range of motion exercises immediately postoperatively is more effective in preventing flexion contractures of the elbow than is delayed treatment.

In vivo measurement of carpal tunnel pressure in the functioning hand.

We recorded directly the pressure within the carpal tunnel during nine different functional positions of the hand and wrist in 102 hands of 92 subjects. Carpal tunnel syndrome was present in 81 hands, and 21 served as controls. A significant rise in pressure was recorded not only with wrist flexion but also with wrist extension, making a fist, holding objects, and isolated isometric flexion of a finger against resistance. Intratunnel pressure dropped after 1 minute of hand and wrist exercises and remained below the resting pressure for over 15 minutes of continuous measurement. We did not observe a rebound phenomenon. Clinical Application: Non-surgical treatment of carpal tunnel syndrome should also include a significant reduction in making a fist, holding objects, pushing, and isolated finger work such as key punching and typing. Activities that require sustained contracture of finger flexor muscles (eg, grasp and hold) also should be avoided. Brief intermittent wrist and hand exercise is recommended to reduce the intratunnel pressure.

The effect of intercarpal joint motion on wrist motion: are there key joints? An in vitro study.

The contribution of each intercarpal joint individually and as a member of a regional group to total wrist motion was analyzed in 10 fresh, frozen cadaver specimens. Each intercarpal joint had an effect on the total wrist motion, but the contribution of each to the different planes of motion was not equal. The scaphoid-capitate joint had a governing effect on the motion of a region comprised of scaphoid-trapezium, scaphoid-trapezoid, and scaphoid-capitate. The lunate-capitate joint had a governing effect on the motion of a region comprised of the lunate-triquetrum, lunate-capitate, triquetrum-hamate, and hamate-capitate complex. Elimination of motion in either of the key governing joints affected total wrist motion the same as elimination of motion in all the joints in that region. Intercarpal fusion for treatment of ligament injury of the proximal intercarpal row may be limited to the scaphoid-capitate or lunate-capitate joint. There is no need to attempt fusion in all joints of either of the two regions.

Segmental motion of the proximal carpal row: their global effect on the wrist motion.

The contribution of the scapho-lunate and luno-triquetral joints to global wrist motion was studied in 11 fresh-frozen cadaver specimens. The carpus were labeled with metallic markers and the joints were selectively transfixed with wires. The wrist was allowed to follow its natural radial and ulnar deviation during flexion and extension, extension and flexion during radial and ulnar deviation, respectively. The data was collected by means of radiography, goniometric measurement, and computer analysis. The proximal carpal row (the intercalated segment) although anatomically represented as a row, presented through its two intersegmental joints, a definite segmental behavior. Each intersegmental joint of the proximal carpal row influenced global wrist motion in all directions but to a different degree for each plane of motion. The segmental joints within the intercalated segment collectively govern 40% of the wrist flexion, 33% of extension, and 10% of ulnar deviation. The scaphoid through its scapho-lunate link exerts a governing effect on total intersegmental proximal carpal row contribution to the global wrist motion.

Median innervated hypothenar muscle: anomalous branch of median nerve in the carpal tunnel.

A hypothenar motor branch of the median nerve in the carpal tunnel was observed and its motor function was documented by direct intraoperative nerve stimulation in two patients having carpal tunnel releases. The hypothenar branch left the median nerve at the midcarpal tunnel area. It crossed the tunnel superficial to the flexor tendons and penetrated the transverse carpal ligament ulnarly to innervate the abductor digiti quinti. Such branching of the median nerve at this level has not been reported previously. Good visualization of the carpal tunnel and careful dissection of its content even in the so called safe zone ulnar to long axis of palmaris longus tendon is recommended.

Piso-triquetral pain syndrome after carpal tunnel release.

Hypothenar pain was a major complaint in 1.1% of patients 6 months after operation in 500 consecutive carpal tunnel releases. Pain, discomfort, and loss of grip strength was noticed mostly during activities requiring full hand grip or activities associated with use of the heel of the hand, such as pushing up from a chair, or pushing open a door with the flat palm. The pain originated from the piso-triquetral joint, possibly a result of intercarpal alignment change after carpal tunnel release. Pisiform excision was curative, with complete relief of symptoms and return of strength and dexterity. Awareness of this syndrome and systemic evaluation of the piso-triquetral joint preoperatively and postoperatively, as presented here, are essential in the management of this condition.

Perichondrial resurfacing arthroplasty in the hand.

A retrospective study of 36 perichondrial resurfacing arthroplasties, 16 metacarpophalangeal (MP) joints, and 20 proximal interphalangeal (PIP) joints with a minimum follow-up of 3 years was conducted to further define indication and contraindication of this procedure. The overall results for MP joints were 56% good, 25% fair, and 19% revision, and for PIP joints, 55% good, 15% fair, and 30% revision. All arthroplasties for healed pyarthrosis failed. Concomitant tendon repair was a cofactor in the high failure rate. Patient age had a direct influence on the outcome of the arthroplasty. In MP joint arthroplasties, 100% of patients in their 20s had good results and 75% in their 30s had good results. In PIP joint arthroplasties, 75% of patients in their teens and 66% in their 20s had good results. Good results were not recorded in MP or PIP joints for patients older than 40 years of age. Perichondrial resurfacing arthroplasty should be considered contraindicated in the treatment of arthropathies resulting from healed pyarthrosis, systemic diseases with joint involvement, concomitant tendon reconstruction, and age over 40 years. The procedure is indicated and can be utilized in the treatment of traumatic arthritis of the MP and PIP joints of the hand in young individuals.

Elongation of the repair configuration following flexor tendon repair.

A prospective study was carried out to evaluate the status of repair and its relation to the incidence of tenolysis in 91 primary flexor tendon repairs in zone II of the hand in 39 patients. Forty-three flexor tendons were repaired by criss-cross technique and 48 flexor tendons by modified grasp technique. The median increase in the intramarker distance was 1.8 mm for the criss-cross technique and 0.6 mm for the modified grasp technique. Of the flexor tendons repaired by criss-cross technique, 18.5% required tenolysis compared to 6.2% in the group repaired by modified grasp technique. The incidence of tenolysis rose sharply when elongation at the repair site was more than 3 mm for the criss-cross technique and more than 1 mm for the modified grasp configurations. There is a direct correlation between the incidence of tenolysis and the amount of elongation of the repair area.