Robert N. Hotchkiss

Injectable Collagenase Clostridium Histolyticum for Dupuytren's Contracture

BACKGROUND Dupuytrens disease limits hand function, diminishes the quality of life, and may ultimately disable the hand. Surgery followed by hand therapy is standard treatment, but it is associated with serious potential complications. Injection of collagenase clostridium histolyticum, an office-based, nonsurgical option, may reduce joint contractures caused by Dupuytrens disease. METHODS We enrolled 308 patients with joint contractures of 20 degrees or more in this prospective, randomized, double-blind, placebo-controlled, multicenter trial. The primary metacarpophalangeal or proximal interphalangeal joints of these patients were randomly assigned to receive up to three injections of collagenase clostridium histolyticum (at a dose of 0.58 mg per injection) or placebo in the contracted collagen cord at 30-day intervals. One day after injection, the joints were manipulated. The primary end point was a reduction in contracture to 0 to 5 degrees of full extension 30 days after the last injection. Twenty-six secondary end points were evaluated, and data on adverse events were collected. RESULTS Collagenase treatment significantly improved outcomes. More cords that were injected with collagenase than cords injected with placebo met the primary end point (64.0% vs. 6.8%, P < 0.001), as well as all secondary end points (P < or = 0.002). Overall, the range of motion in the joints was significantly improved after injection with collagenase as compared with placebo (from 43.9 to 80.7 degrees vs. from 45.3 to 49.5 degrees, P < 0.001). The most commonly reported adverse events were localized swelling, pain, bruising, pruritus, and transient regional lymph-node enlargement and tenderness. Three treatment-related serious adverse events were reported: two tendon ruptures and one case of complex regional pain syndrome. No significant changes in flexion or grip strength, no systemic allergic reactions, and no nerve injuries were observed. CONCLUSIONS Collagenase clostridium histolyticum significantly reduced contractures and improved the range of motion in joints affected by advanced Dupuytrens disease. (ClinicalTrials.gov number, NCT00528606.)

The Unstable Elbow

### Pathoanatomy The pathoanatomy of an elbow dislocation can be thought of as a disruption of the circle of soft tissue or bone, or both, that begins on the lateral side of the elbow and progresses to the medial side in three stages (Fig. 1-A). In stage 1, the lateral collateral ligament is partially or completely disrupted (the ulnar part is disrupted). This disruption results in posterolateral rotatory subluxation of the elbow, which can reduce spontaneously (Fig. 1-B). Stage 2 involves additional disruption anteriorly and posteriorly. There is an incomplete posterolateral dislocation of the elbow in which the concave medial edge of the ulna rests on the trochlea. On a lateral radiograph of the elbow, the coronoid process appears to be perched on the trochlea. This dislocation can be reduced with use of minimal force or by the patient manipulating his or her own elbow. Stage 3 is subdivided into three parts. In stage 3A, all of the soft tissues around and including the posterior part of the medial collateral ligament are disrupted, leaving only the important anterior band (the anterior medial collateral ligament) intact. This permits posterior dislocation by a posterolateral rotatory mechanism. The elbow pivots on the intact anterior band of the medial collateral ligament. Reduction is accomplished by gentle manipulation of the elbow beginning with supination and valgus stress, temporarily recreating the deformity, followed by application of traction, varus stress, and pronation simultaneously. The intact anterior medial collateral ligament provides stability if the forearm is kept in pronation to prevent posterolateral rotatory subluxation during valgus stress-testing. Stage-3A instability is most commonly seen in the presence of fractures of the radial head and coronoid process. In stage 3B, the entire medial collateral complex is disrupted. Varus, valgus, and rotatory instability are all present following reduction. In stage 3C, the instability …

The utility of high-resolution magnetic resonance imaging in the evaluation of the triangular fibrocartilage complex of the wrist.

We performed a prospective study in order to assess the utility of high-resolution magnetic resonance imaging in the detection and specific localization of tears of the triangular fibrocartilage complex. Seventy-seven patients who had pain in the wrist were studied with use of a dedicated surface coil and three-dimensional gradient-recalled techniques with a field of view of eight centimeters and a slice thickness of one millimeter. The patients had pain on the ulnar side of the wrist, ligamentous instability, occult ganglia, or a combination of these. Magnetic resonance images were assessed for radial or ulnar avulsion, or both; central defects; degenerative intrasubstance changes; and complex tears of the triangular fibrocartilage complex. Partial tears were differentiated from complete tears. The findings on the magnetic resonance images were then compared with the arthroscopic findings. Fifty-seven of the fifty-nine tears that were suspected on magnetic resonance images were confirmed with arthroscopy; the two suspected tears that were not confirmed had been interpreted as small partial tears on the magnetic resonance images. With use of arthroscopy as the standard, magnetic resonance imaging had a sensitivity of 100 per cent (fifty-seven of fifty-seven), a specificity of 90 per cent (eighteen of twenty), and an accuracy of 97 per cent (seventy-five of seventy-seven) for the detection of a tear (&kgr; = 0.93, p < 0.00001). Fifty-three of the fifty-seven tears were localized correctly with use of magnetic resonance imaging. With regard to the location of the tear, magnetic resonance imaging had a sensitivity of 100 per cent (fifty-three of fifty-three), a specificity of 75 per cent (eighteen of twenty-four), and an accuracy of 92 per cent (seventy-one of seventy-seven) (&kgr; = 0.9, p < 0.0001). We concluded that high-resolution magnetic resonance imaging permits accurate depiction and localization of tears of the triangular fibrocartilage complex. When the appropriate pulse sequence is used, magnetic resonance imaging is an accurate and effective method for the non-invasive evaluation of pain in the wrist.

Alternative operative exposures of the posterior aspect of the humeral diaphysis with reference to the radial nerve.

An anatomical study was performed to define the course of the radial nerve in the posterior aspect of the arm, with particular reference to its relationship to operative exposures of the posterior aspect of the humeral diaphysis. In ten cadaveric specimens, the radial nerve was found to cross the posterior aspect of the humerus from an average of 20.7 ± 1.2 centimeters proximal to the medial epicondyle to 14.2 ± 0.6 centimeters proximal to the lateral epicondyle. As it crossed the posterior aspect of the humerus in each specimen, the nerve had several branches to the lateral head of the triceps; however, no branches were found innervating the medial head of the triceps in the posterior aspect of any of the specimens. At the lateral aspect of the humerus, the nerve trifurcated into a branch to the medial head of the triceps, the lower lateral brachial cutaneous nerve, and the continuation of the radial nerve into the distal part of the upper arm and the forearm. Three operative approaches were performed in each specimen. The posterior triceps-splitting approach exposed an average of 15.4 ± 0.8 centimeters of the humerus from the lateral epicondyle to the point at which the radial nerve crossed the posterior aspect of the humerus. For the second approach, the radial nerve was mobilized proximally to allow an additional six centimeters of the humeral diaphysis to be visualized. The third approach (the modified posterior approach) involved the identification of the radial nerve distally as it crossed the lateral aspect of the humerus, followed by reflection of both the lateral and the medial heads of the triceps medially. This exposure permitted visualization of 26.2 ± 0.4 centimeters of the humeral diaphysis from the lateral epicondyle proximally. The results after use of the modified posterior approach in seven patients were also reviewed.

Radioulnar Load-Sharing in the Forearm. A Study in Cadavera*

Custom-designed miniature load-cells were inserted into the distal end of the ulna and the proximal end of the radius in ten fresh-frozen forearms from cadavera. The forces transmitted through the bones at these sites were measured under 134 newtons of constant axial load that was applied through the metacarpals as the forearm was rotated from 60 degrees of supination to 60 degrees of pronation. The simultaneous measurements of these forces allowed the calculation of radioulnar load-sharing at the wrist and the elbow as well as the calculation of the amount of force that was transferred from the radius to the ulna through the interosseous membrane. With the elbow in valgus alignment (that is, with contact between the radial head and the capitellum), the main pathway for load transmission through the forearm was direct axial loading of the radius; measurements from both load-cells were unaffected by the angle of elbow flexion. When the forearm was in neutral rotation, the mean force in the distal end of the ulna averaged 2.8 per cent of the load applied to the wrist and the mean force in the proximal end of the ulna averaged 11.8 per cent; this indicated that only a small amount of tension developed in the interosseous membrane. With the elbow in varus alignment (that is, with no contact between the radial head and the capitellum), load was transmitted through the forearm by a transfer of force from the radius to the ulna through the interosseous membrane. When the forearm was in neutral rotation, the force in the distal end of the ulna averaged 7.0 per cent of the load applied to the wrist and the force in the proximal end of the ulna averaged 93.0 per cent; the force through the interosseous membrane decreased with supination of the forearm. Testing with the elbow in valgus alignment and shortening of the distal end of the radius in two-millimeter increments produced corresponding increases in force in the distal end of the ulna and decreases in force in the radial head. The forces through the interosseous membrane remained low after each amount of radial shortening. CLINICAL RELEVANCE: Transfer of load from the wrist, through the radius and the ulna, to the elbow is a complex event that depends on the position of the forearm, anatomy of the wrist, and soft-tissue linkages between the radius and the ulna. Varus-valgus alignment of the elbow influences the basic mechanism of force transmission through the forearm. The interosseous membrane plays a minimum role in load transmission with the elbow in valgus alignment. Dynamic gripping activities that include varus stress to the elbow would be expected to develop force in the interosseous membrane. Radioulnar load-sharing at the wrist and the elbow changed significantly when the distal end of the radius was shortened by as little as two millimeters (p < 0.05). With the elbow in valgus alignment, four millimeters of shortening was required to approximately balance the radioulnar loads at the wrist.

Prosthetic radial head components and proximal radial morphology: A mismatch

A morphometric study of the proximal radius was performed with magnetic resonance imaging scans to measure the anatomic dimensions of the radial head and neck. These dimensions were then compared with the manufacturers size specifications of commercially available titanium prosthetic radial head components to determine whether these designs adequately match the morphologic characteristics of the proximal radius. A cadaveric correlation was performed to validate the accuracy and reliability of measurements obtained from the magnetic resonance scans. The narrow intramedullary dimensions of the radial neck negated fitting of even the smallest available metallic prosthetic component stem in 18 (39%) of 46 scans reviewed (confidence interval 26% to 53%). Of the 31 male patients who underwent scanning, 4 (13%) would not be able to be fitted with a prosthetic component according to the manufacturers technique guide (confidence interval 0% to 29%). Of the 15 female patients who underwent scanning, 14 (93%) would not able to be fitted with a prosthetic stem (confidence interval 70% to 99%). In those patients in whom the radial neck could accommodate a prosthetic stem (n = 26), there was ineffective restoration of proximal radial head length in all cases (100%, confidence interval 87% to 100%). The average shortening was 4 mm of proximal radial length (range 1 to 7 mm). Our findings reveal that the commercially available metallic radial head design may overestimate the dimensions of the radial neck. Inadequate sizing of radial head prostheses may lead to an inadvertent change in proximal radial length, with potentially adverse effects on elbow, forearm, and wrist mechanics. Newer designs taking into account these anatomic dimensions may lead to an improvement in function after reconstruction.

Wide excision of the distal ulna: A multicenter case study

Excision of the distal ulna to treat degenerative disease or instability has fallen into disfavor following reports of radioulnar impingement, carpal instability, and distal ulnar instability. Alternative procedures for reconstruction of the painful distal ulna have been developed to address these problems; the results have been generally favorable. When faced with distal ulnar reconstruction that has failed after multiple surgical procedures, or a distal ulnar neoplasm, the surgeon is left with few treatment options. Creation of a one-bone forearm, free fibular transfer, and allograft replacement have been attempted, with mixed outcomes. We report the results of 5 men and 7 women who underwent wide excision of the distal ulna, defined as surgical excision of 25% to 50% of the ulnar length. The diagnosis was failed distal radioulnar reconstruction or excision in 8 patients, osteomyelitis in 1, congenital pseudoarthrosis of the radius in 1, and neoplasm in 2. No soft tissue reconstruction was performed. Patients were examined at an average of 22 months after surgery for radiocarpal and radioulnar instability, functional outcome, pain relief, grip strength, and range of motion. Nine of the 12 procedures resulted in good or excellent results; 1 patient had a fair result after resection for osteosarcoma, and the procedure in 2 patients failed, requiring conversion to a one-bone forearm. Grip strength was restored to 75% of the normal side and range of motion was restored to 86% of the normal side. Wide excision of the distal ulna without soft tissue reconstruction is a simple and durable treatment of neoplasms of the distal ulna or salvage of the failed reconstruction of the distal radioulnar joint. We do not recommend its use in patients with incompetency or disruption of the interosseous membrane.

The use of frozen-allograft radial head replacement for treatment of established symptomatic proximal translation of the radius: preliminary experience in five cases.

Five patients with disabling symptoms related to proximal translation (> 1 cm) of the radius following radial head excision (Essex-Lopresti lesion) were treated with implantation of a frozen-allograft radial head prosthesis. Following restoration of neutral ulnar variance at the wrist, a size-matched frozen radial head allograft was implanted and secured to the proximal radius with internal fixation. In three patients, this was a two-stage procedure; radial length was restored gradually using an ilizarov external fixation device and the allograft was placed later. Patients were evaluated clinically and radiographically at a mean follow-up time of 3 years (range, 1-7 years). All patients had relief of wrist and elbow pain and were satisfied with the outcome of the operation. Forearm rotation improved by a mean of 37 degrees and wrist motion improved by a mean of 45 degrees. Forearm reconstruction with frozen radial head allograft implantation may be a beneficial method of treatment for this difficult problem.

Indications and Reoperation Rates for Total Elbow Arthroplasty: An Analysis of Trends in New York State

BACKGROUND Total elbow arthroplasty was originally used to treat patients with arthritis. As familiarity with total elbow arthroplasty evolved, the indications were expanded to include other disorders. There continues to be a low number of total elbow arthroplasties performed each year in comparison with hip, knee, and shoulder arthroplasties, and few large studies have examined the indications and associated complications of total elbow arthroplasty. The purposes of this study were to evaluate the changes with time in the indications for total elbow arthroplasty and to examine the complications of this procedure in a large database. METHODS The Statewide Planning and Research Cooperative System database from the New York State Department of Health, a census of all ambulatory and inpatient surgical procedures in the state of New York, was used to identify individuals who underwent primary total elbow arthroplasty during the time period of 1997 to 2006. These total elbow arthroplasties were evaluated for admitting diagnoses, sex and age of patient, readmission and complication data, and time to subsequent elbow surgery. RESULTS From 1997 to 2006, there were 1155 total elbow arthroplasties performed in New York State. In 1997, 43% of the total elbow arthroplasties were associated with trauma and 48%, with inflammatory conditions. In 2006, this changed to 69% and 19%, respectively. Within ninety days after the primary total elbow arthroplasty, 12% of the patients were readmitted to the hospital with approximately one-half (5.6%) admitted for problems related to the total elbow arthroplasty. The overall revision rate was 6.4%. The revision rates for the traumatic, inflammatory arthritis, and osteoarthritis groups were 4.8%, 8.3%, and 14.7%, respectively. Of particular interest, 90.5% of the total elbow arthroplasties were performed by surgeons with no recorded experience in the database, which began collecting these data in 1986. CONCLUSIONS This study provides useful information regarding patients undergoing total elbow arthroplasty in New York State. During the study period, the most common indication for total elbow arthroplasty changed from inflammatory arthritis to trauma. Although the number of total elbow arthroplasties being performed each year has increased, there continues to be a high complication and revision rate.

Hinged elbow external fixators: indications and uses.

Abstract Hinged external fixation of the elbow joint can play an important role in managing complicated fracture‐dislocations, joint instability after extensive contracture release, and distraction interposition arthroplasty. Application of these devices requires accurate alignment of the fixator axis with the anatomic axis of the elbow. The primary therapeutic goal is to allow joint motion while protecting the healing ligaments. Common complications include pin loosening, injury to adjacent neurovascular structures, cellulitis, and loss of reduction. Although reported data are limited, this technique is a useful adjunct in patients with complex elbow instability.