William F. Blair

Measuring ulnar variance: A comparison of techniques

This study compared three commonly used methods of measuring ulnar variance. The comparison included the project- a-line technique (A), the method of concentric circles (B), and the method of perpendiculars (C). Specific features studied were variations in results generated by each technique as well as the interobserver and intraobserver reliability for each technique. The only significant difference among techniques was between techniques A and B (p = 0.0224), where mean A values were more positive than mean B values. Observers were found to differ significantly (p = 0.0092) independent of technique. All methods studied were highly reliable, although the method of perpendiculars was most reliable for both interobserver (reliability = 0.9801) and intraobserver (reliability = 0.9719) reliability. This study shows that the clinician may choose whichever technique he prefers when measuring ulnar variance.

Long-term results of extensor tendon repair

A retrospective analysis was done in 62 patients with 101 digits having extensor tendon injury. Quality of outcome and parameters that might influence outcome were evaluated. The majority of patients were treated with conventional static splinting. Sixty percent of all fingers sustained an associated injury (fracture, dislocation, joint capsule or flexor tendon damage). Patients without associated injuries achieved 64% good/excellent results, and total active motion of 212 degrees. This difference was statistically significant (p less than 0.05). Distal zones (1 to 4) had a significantly poorer result than more proximal zones (5 to 8). The percentage of fingers losing flexion was greater than the percentage of fingers losing extension. In addition, the average degree loss of flexion was greater than the average degree loss of extension. This would seem to indicate that loss of flexion may be a more significant complication from extensor tendon injury than previously thought.

The scapholunate ligament

The effects of scapholunate ligament sectioning on scaphoid and lunate bone three-dimensional kinematics were analyzed using a sonic digitizer method. Carpal bone motions were described using a screw displacement axis concept. After scapholunate ligament sectioning, few significant kinematic changes were observed in the orientation of the screw displacement axes or in carpal bone rotation about the screw displacement axes. The angles between the screw displacement axes of the scaphoid and lunate bones were only minimally affected, indicating that the two bones continued to track well relative to each other. The results indicate that sectioning of the scapholunate ligament does not result in a major disturbance of scaphoid and lunate bone motions.

Technical factors related to Herbert screw fixation

We reviewed 24 patients treated for an acute fracture or a nonunion of the scaphoid bone using the Herbert screw. Mean follow-up in 22 patients who returned for examination was 17 months. The overall union rate was 67% for both acute fractures and nonunions. Fracture healing correlated strongly with technical factors of the procedure. The fracture failed to heal in seven of nine cases with poor scaphoid realignment, inaccurate jig placement, or improper screw length for a nonunion rate of 78%. Conversely, without these technical problems, 14 (93%) of 16 fractures achieved union. Applying Herberts criteria, a satisfactory rating for clinical function was achieved in 59% of all patients and for patient satisfaction in 68% of all patients. Although the postoperative immobilization period was reduced using the screw, the final functional result in our nonunions was similar to that reported for the Russe bone grafting procedure. Appropriate modifications of the standard technique and recognition of equipment limitations may improve union rates.

An In-Vivo Study of Normal Wrist Kinematics

The motion of the hand relative to a reference frame embedded in the radius is described using the screw displacement axis (SDA) concept. A three-dimensional sonic digitizer was utilized in a study of the dominant wrist of 15 normal subjects to determine the location and orientation of the SDAs based on the endpoints of flexion-extension motion (FEM) and radial-ulnar deviation (RUD) of the hand. The length of the common perpendicular between the SDAs of FEM and RUD was as large as 6 mm in some individuals; however, in some subjects the FEM SDA was distal of the RUD SDA while in others it was proximal. Considering the group of 15 subjects, the SDAs of FEM and RUD for the normal group nearly intersect in the head of the capitate in the neutrally positioned wrist and forearm.

Digital Periarterial Sympathectomy for Ischaemic Digital Pain and Ulcers

Digital periarterial sympathectomy was performed on 11 digits in three patients with chronic digital ischaemia which was a manifestation of either Raynaud’s disease, C.R.E.S.T. syndrome or traumatic ulnar artery thrombosis. Before operation, all patients had pain in the affected fingers and five digits had ulcers, two of which were infected. Using the operating microscope, the adventitia was stripped circumferentially over the distal 2 cm. of the common digital arteries, the bifurcation and the proximal 1 cm. of the proper digital arteries distal to the bifurcation. The same procedure was repeated, at the wrist level, for the ulnar artery and/or the radial artery and its dorsal branch. Follow-up ranged from three to 16 months. After two weeks, all patients reported relief of pain and the ulcers were progressively healing. By three months, all ulcers had healed.

Electromyographic changes after carpal tunnel release

This prospective clinical study was designed to quantitate post-carpal tunnel release electromyographic (EMG) changes in the median nerve, and changes in static two-point discrimination, pinch strength, and grip strength. Carpal tunnel release was performed in 54 hands of 36 patients (average age of patients was 44.6 years). The EMG and clinical studies were completed just before surgery, at 2 weeks, and then at postoperative periods of 3, 6, 9, 12, 18, and 24 months. The sensory latencies and motor latencies were significantly (p less than 0.05) improved at the 3- and 6-month postoperative periods, respectively. The motor and sensory conduction velocities were significantly (p less than 0.05) improved as early as 2 weeks postoperatively. Two-point discrimination values were significantly (p less than 0.05) improved at 2 weeks postoperatively. For the pinch and grip strengths, significant (p less than 0.05) improvement did not occur until the 6- and 9-month postoperative periods, respectively. These results should be of considerable value, especially in the evaluation of the post-carpal tunnel release patient with persistent or recurrent symptoms.

Low-velocity gunshot wounds to extremities

Several therapeutic modalities in the management of low-velocity gunshot wounds to extremities were investigated. Local excision of wound margins, irrigation, and primary or delayed primary closure without the use of the operating room or prophylactic antibiotics produced results which were comparable to those obtained with a more aggressive surgical protocol.

Proximal interphalangeal joint arthroplasty.

Prosthetic implant arthroplasty of the proximal interphalangeal (PIP) joint has a limited role in the reconstruction of the rheumatoid hand. Ninety-three PIP joint arthroplasties, including 56 Flatt, 30 Swanson, and seven Niebauer implants, were reviewed with postoperative follow-up periods averaging 6.2 years. The average maximum extension/flexion for the prostheses were Flatt, 28 degrees/45 degrees; Swanson, 1 degree/40 degrees; and Niebauer, 3 degrees/26 degrees. The average active ranges of motion for the prosthetic groups were Flatt, 15 degrees; Swanson, 37 degrees; and Niebauer, 19.5 degrees. Analysis of active motion at intervals of up to ten years indicated gradually decreasing active motion for each prosthesis. Comparison of preoperative motion with motion three years after operation indicated a decrease in the Flatt prosthesis group, from 35 degrees to 20 degrees. Radiographically, cortical perforation by the prosthesis was common with the Flatt prosthesis (80%), and recurrent swan-neck deformity was frequent with the Swanson spacer (27%). Despite suboptimal clinical results, patient satisfaction was high, and the ability of patients to perform activities of daily living was acceptable.

Schultz metacarpophalangeal arthroplasty: A long-term follow-up study

We describe a prospective, long-term evaluation of the Schultz metacarpophalangeal joint implant. The prosthesis is a semiconstrained, cemented implant with a ball-in-socket articulation. Thirty-six implants were followed for an average of 10.9 years. There was a progressive decrease in range of motion and strength and a recurrence of ulnar deviation. The neck of the proximal phalangeal component fractured in 39% of the joints. Periarticular heterotopic bone formed in all joints, but was extensive in only 22%. Although some lucency of the bone-cement interface was seen in 80% of the joints, no prosthetic loosening occurred in this series. Our results indicate that long-term, intramedullary cement fixation of relatively long-stemmed components can be satisfactory. However, the articulated portion of this implant does not consistently withstand the stresses transmitted across the joint and does not provide long-term joint stability.