Martin A. Posner

Cold exposure injuries to the extremities

&NA; Cold exposure injuries comprise nonfreezing injuries that include chilblain (aka pernio) and trench, or immersion, foot, as well as freezing injuries that affect core body tissues resulting in hypothermia of peripheral tissues, causing frostnip or frostbite. Frostbite, the most serious peripheral injury, results in tissue necrosis from direct cellular damage and indirect damage secondary to vasospasm and arterial thromboses. The risk of frostbite is influenced by host factors, particularly alcohol use and smoking, and environmental factors, including ambient temperature, duration of exposure, altitude, and wind speed. Rewarming for frostbite should not begin until definitive medical care can be provided to avoid repeated freeze‐thaw cycles, as these cause additional tissue necrosis. Rewarming should be rapid and for an affected limb should be performed by submersion in warm water at 104° to 107.6°F (40° to 42°C) for 15 to 30 minutes. Débridement of necrotic tissues is generally delayed until there is a clear demarcation from viable tissues, a process that usually takes from 1 to 3 months from the time of initial exposure. Immediate escharotomy and/or fasciotomy is necessary when circulation is compromised. In addition to the acute injury, frostbite is associated with late sequelae that include altered vasomotor function, neuropathies, joint articular cartilage changes, and, in children, growth defects caused by epiphyseal plate damage.

Tumorlike Lesions and Benign Tumors of the Hand and Wrist

&NA; A broad spectrum of tumorlike lesions and neoplasms can occur in the hand and wrist, although with somewhat less frequency than in other parts of the body. A thorough understanding of the differential diagnosis of these lesions and a comprehensive strategy for evaluation are central for effective care. Plain radiographs are diagnostic for most bony lesions, whereas magnetic resonance imaging may be necessary to help differentiate a benign soft‐tissue lesion from the rare malignant neoplasm. In spite of the complex anatomy, adherence to proper oncologic principles most often will lead to a satisfactory outcome.

Cortico-medullary continuity in bizarre parosteal osteochondromatous proliferation mimicking osteochondroma on imaging.

Bizarre parosteal osteochondromatous proliferation (BPOP), or Nora’s lesion, is an unusual surface-based lesion of bone found most commonly in the hands and feet. In the original description of the lesion and in all publications that followed, one of the key imaging characteristics used to define this entity was the lack of cortico-medullary continuity with the underlying bone. The authors present 4 unique cases of pathologically proven BPOP in which cortico-medullary continuity with the underlying bone was demonstrated on imaging. It is believed that florid reactive periostitis, BPOP and turret osteochondroma may reflect points along the same continuum with trauma the likely inciting event. The authors suggest that, given this continuum, it may be possible to have BPOP lesions demonstrating overlapping imaging features with osteochondroma. If this is the case, strict adherence to the standard imaging criterion of lack of continuity between the lesion and the underlying bone may lead to misdiagnosis of these unusual cases of BPOP as osteochondromas.

Comparison of a suture technique with the modified Kessler method: Resistance to gap formation☆

We performed an in vitro study using canine flexor tendons to compare the tensile properties of a suture technique for flexor tendon repair with the standard modified Kessler technique. The technique employs a central wire loop that connects the two transverse limbs of the modified Kessler suture. Both techniques were studied with and without a Lembert epitendinous stitch. The technique combined with an epitendinous suture provided the strongest resistance to gap formation, and its load at gap initiation was 100% greater than the load in tendons repaired with the modified Kessler and an epitendinous suture. Because of its increased resistance to gap formation, this suture technique may provide a safer margin for controlled early active motion after flexor tendon repair.

Treatment of enchondromas of the hand with allograft bone.

We investigated whether cortico-cancellous allograft obtained from cadaveric banked bone is effective in the treatment of enchondroma of the hand. Twelve patients had 15 operations on 19 enchondromas using allograft bone. These patients were compared with 16 patients with enchondroma treated with autogenous iliac cancellous bone. The distribution of tumors was similar in both groups. There was no significant difference in the patients age, their occupations, or whether the operation involved the dominant hand. In both groups, immobilization was maintained until clinical union was obtained. The duration of immobilization for both groups was identical. There were no recurrences, refractures, or complications in patients treated with allograft bone. The grafts incorporated and remodeled in all patients. We concluded that a allograft cortico-cancellous bone can be used effectively in the treatment of enchondromas of the hand. It is especially useful in the treatment of patients with multiple tumors.

Lipofibroma of the median nerve: A report of two cases

Two cases of lipofibroma of the median nerve are described. The literature is reviewed and the clinical and treatment aspects of this unusual condition are discussed.

Irreducible dorsal dislocations of the proximal interphalangeal joint

Dorsal dislocations of the proximal interphalangeal joint are common injuries, and reduction is usually obtained by manipulation. We describe four cases of dorsal dislocation in which attempts at reduction by manipulation were not successful. Three of these injuries were open and one was closed. At surgery, the main block to reduction in all cases was the palmar plate that had ruptured from its proximal attachment and was interposed between the joint surfaces.

Malignant Tumors of the Hand and Wrist

&NA; Malignant tumors in the hand and wrist compose a wide variety of lesions involving skin, soft tissues, and bone. Although these lesions are found elsewhere in the body, many have unique characteristics at this anatomic location. Skin tumors predominate; the most common are squamous cell carcinomas, followed in frequency by basal cell carcinomas and malignant melanomas. Other soft‐tissue malignancies are less common but may present more difficult diagnostic problems. They often appear as painless masses that sometimes have been present for months or even years and deceptively appear to be benign. A missed or delayed diagnosis of these tumors can have devastating consequences. Bone malignancies involve both primary lesions, of which chondrosarcomas are the most common, and metastatic lesions. Regardless of cell type, treatment of malignant tumors in the hand and wrist requires special considerations because of the important function of these structures. Orthopaedic surgeons should be familiar with the spectrum of these tumors, the work‐up necessary to arrive at a precise diagnosis, and the treatment that will achieve the most favorable outcome.

A New Technique for Reconstruction of the Ulnar Collateral Ligament of the Thumb

Background Several previous studies have described reconstructive methods for the treatment of an injury to the ulnar collateral ligament of the thumb. However, there are few biomechanical studies to date to analyze the strength of the surgical reconstruction. Purpose To evaluate 2 reconstruction techniques with use of a cadaveric model (1) reconstruction with the use of a free tendon graft placed in a figure-of-8 fashion through drill holes in the metacarpal and proximal phalanx of the thumb, and (2) reconstruction with the use of the Bio-Tenodesis Screw System. Study Design Controlled laboratory study. Methods Eight matched pairs of cadaveric specimens underwent removal of the proper and accessory ulnar collateral ligaments. One of the 2 reconstruction methods was performed, and specimens were mounted on a materials-testing machine. The specimens were subjected to valgus stress to failure at 30° of flexion. Failure was defined as valgus laxity of 30° at the metacarpophalangeal joint. Results The peak load to failure was 23.5 ± 11.4 N for the figure-of-8 reconstruction and 24.3 ± 12.3 N for the reconstruction using the Bio-Tenodesis Screw System. Comparing the 2 groups, there was no statistically significant difference in peak loads to failure (P = .88). Conclusion There was no statistically significant difference between the peak loads to failure of the 2 reconstructions. Clinical Relevance The Bio-Tenodesis Screw System may provide another viable option for surgical reconstruction of the ulnar collateral ligament of the thumb.

Glomus tumors of the wrist

Glomus tumors about the wrist area are rare. Three new cases are presented. A provocative diagnostic test using ethyl chloride spray has been found useful. This test is superior to the use of ice because application can be to a very small area.