SLAC wrist in the absence of recognised trauma and CPPD.

PURPOSE: This comparative cohort study was designed to determine whether non-traumatic SLAC wrist exists, and is associated with abnormal carpal bone kinematics (specifically, decreased lunate flexion). METHODS: SLAC patients with no recognised history of upper extremity trauma were prospectively compared with an age-matched control group. RESULTS: Thirty-five subjects (69 wrists), included 33 non-traumatic SLAC wrists and 36 control wrists. The non-traumatic SLAC group had significantly different radiographic kinematic analysis compared to the control group. Flexion of the asymptomatic non-degenerative wrist of the non-traumatic SLAC group was distributed 70% through the lunocapitate (LC) joint and only 30% through the RL joint (p < 0.05). Conversely, flexion was more evenly distributed in the control group (48% LC and 52% RL). The non-traumatic SLAC group had abnormal wrist kinematics even in the non-involved side. CONCLUSIONS: This study suggests that non-traumatic SLAC does exist. We believe that non-traumatic SLAC begins with abnormal wrist kinematics and that the dorsal radiolunate ligament restricts lunate flexion but not scaphoid flexion, leading to increased SL angles and, with years, eventual attrition of the SL ligament.

Systemic fat and thrombus embolization in patients undergoing total knee arthroplasty with regional heparinization.

A double-blind, randomized, controlled study was undertaken to determine if a technique of intraoperative anticoagulation would decrease the incidence or severity of venous embolization after tourniquet release during total knee arthroplasty. Sixty-six patients were randomized to receive either the heparin or placebo treatment. Transesophageal echocardiography was performed before and after tourniquet release to detect embolic material in the right atrium. Transient opacification of the right atrium was observed in all patients within the first 30 seconds after tourniquet release. Regional limb heparinization is not effective in reducing the intensity of right atrium opacification because much of the echogenic material was composed of fat rather than thrombus.

The treatment of pseudoarthrosis of the scaphoid by bone grafting and three methods of internal fixation.

OBJECTIVES: To measure the rate of union in patients with pseudoarthosis of the scaphoid, treated with trapezoidal bone grafting as outlined by Fernandez and 1 of 3 methods of internal fixation and to compare unions versus nonunions and potential predictors of union to determine if associations exist. DESIGN: A retrospective radiologic study of scaphoid pseudoarthroses. SETTING: Division of Orthopedic Surgery, Ottawa Hospital, General Site, a tertiary care facility. PATIENTS: Thirty-four patients with nonunion of scaphoid fractures, treated between 1990 and 1997, with an average follow-up of 19.8 months. INTERVENTIONS: Trapezoidal bone grafting and internal fixation with Kirschner (K) wires, an AO cannulated screw or a Herbert screw. OUTCOME MEASURES: The time to union of scaphoid pseudoarthroses and predictors of union, including the classification, location of pseudoarthrosis, type of internal fixation and length of bone graft. RESULTS: The results showed a correlation between the classification and location of the fracture as determined radiologically, and the outcome. There was no correlation between the type of internal fixation used and the outcome, or between the length of the bone graft and the outcome. Twenty-three patients had radiologically demonstrated union after a mean time of 8.2 months; 16 of 24 patients achieved successful union when treated with K-wire implants, after a mean time of 7.2 months. CONCLUSIONS: Trapezoidal bone grafting and internal fixation with K wires is a practical technique, classification and location of the fracture notwithstanding. Time to union is long, and the results may be unpredictable. Use of K wires for internal fixation presents the clinician with an alternative to fixation with either the AO cannulated screw or the Herbert screw, and has the advantages of cost, ease of insertion and accessibility. This method may therefore be the treatment of choice in developing countries. Resection of the area of pseudoarthrosis must include all fibrous tissue and sclerotic bone. The length of graft, within the parameters of this study, did not affect the outcome.

Self-reported disability following distal radius fractures: the influence of hand dominance.

The purpose of this study was to record the spectrum of self-reported disability following distal radius fractures and to gauge for differences in hand dominance in the use of subjective outcome data. Items were generated through patient interviews, literature review, and peer consultation. Fifty-three items were evaluated by a group of 55 patients recovering from a fracture of the distal radius, which established the prevalence, mean severity score, and overall severity score (or impact) of each item as it related to physical function and social/emotional impact. Hand dominance, age, and gender were also recorded. The results confirm that many patients who sustain distal radius fractures experience substantial impairment across a spectrum of quality of life domains. Because patients who sustain a dominant wrist injury are likely to report greater functional impairment across a wider range of activities, they also possess a greater potential for improvement. The practical implication is that outcome studies for the treatment of distal radius fractures should take hand dominance into account.

Histologic analysis of fetal ulnar variance.

Twenty-eight fetal wrists aged 5 to 21 weeks gestation were examined histologically to assess ulnar variance. There was a trend from ulna negative to ulna neutral among this population. Of 10 wrists in group I (5-8 weeks gestation), 8 were ulna negative and 2 were ulna neutral. Of nine wrists in group II (11-13 weeks gestation), three were ulna negative and six were ulna neutral. Of nine wrists in group III (18-21 weeks gestation), two were ulna negative and seven were ulna neutral. Overall, 13 embryos demonstrated an ulna negative variance; the remainder had ulna neutral variance. These results are significantly different than the incidence of ulnar variance in adults. With growth, factors must occur that change this fetal relationship of radius to ulna.

Objective comparison of manual dexterity in physicians and surgeons.

Recent interest in the assessment of manual dexterity of surgical residency applicants prompted an investigation of psychomotor skills in surgeons and physicians. The Purdue Pegboard and Minnesota Manual Dexterity tests were given to 57 subjects. Analysis of the data revealed no significant difference in dexterity between medical and surgical residents, suggesting that medical students do not select specialty training programs because of the presence or absence of manual skills. The data also revealed that surgical staffmen performed substantially worse than those in the other groups on some of the tests, possibly because of an older average age. The authors conclude from their data that manual dexterity tests should not be used in assessing candidates for surgical residency training positions.

Expected contamination of the orthopedic surgeon's conjunctiva.

Likely contamination of a surgeon's conjunctiva by patients' body fluids is surprisingly frequent. Blood and fat are the most common agents but cellular implantation may occur. Possible contamination was documented in 37 of 60 orthopedic procedures. Power tools, hammering and the use of rongeurs are the main culprits in producing a forced spray most likely to cause contamination. Reduction of the hip at the time of replacement arthroplasty is often associated with propulsion of blood. Not a single case of possible contamination resulted from the pumping action of a severed vessel. Since orthopedic surgeons work in a high-risk environment, safety glasses are recommended to prevent contraction of viral diseases such as hepatitis B and acquired immune deficiency syndrome by way of the conjunctiva. The glasses will also protect the surgeon from bacterial and cellular conjunctival contamination, in addition to preventing physical damage secondary to propelled bone and cement.

The relationship between oblique fractures of the medial malleolus and concomitant fractures of the anterolateral aspect of the tibial plafond.

Considerable disagreement exists concerning the mechanism by which the relatively uncommon oblique fracture of the medial malleolus is produced, and to our knowledge the relationship between it and a fracture of the anterolateral aspect of the tibial plafond has not previously been recognized. We treated a patient with these fractures whose deformed steel-reinforced work boot indicated that the mechanism of injury had been external rotation, dorsiflexion, and abduction. We found this fracture pattern in eleven other patients. We concluded that the malleolar fracture is an oblique avulsion injury and that impingement of the talus on the anterolateral aspect of the tibial plafond accounts for the other fracture. The identification of an oblique medial malleolar fracture should prompt a search for a fracture of the anterolateral aspect of the tibial plafond; the reverse is also true.

Irradiation of the surgeon during pinning of femoral fractures.

The intensity of scattered radiation in both a forward and a backward direction from a portable fluoroscope during pinning of the neck of the femur was measured by experiments on a cadaver. The intensity decreased rapidly with increasing distance from the flare of the greater trochanter. Hazard to the surgeon's hands from scattered radiation can be greatly reduced by positioning the C-arm of the fluoroscope so that the x-ray beam is directed laterally.