Efficacy of combined local mechanical vibrations, continuous passive motion and thermotherapy in the management of osteoarthritis of the knee.

OBJECTIVES: We evaluated the efficacy of combined mechanical vibrations, continuous passive motion (CPM) and heat on the severity of pain in management of osteoarthritis of the knee (OA-K). METHODS: In this controlled, double crossover study, 71 OA-K patients were randomized in Phase 1 to receive 4 weeks active treatment consisting of two 20-min sessions per day (34 patients, Group AB) or treatment with a sham device (37 patients, Group BA). This was followed by a 2-week washout period (Phase 2). In Phase 3, patients crossed over so that Group AB was treated with the sham device and Group BA received active treatment for an additional 4 weeks. Patient assessments of pain (visual analog scale, VAS) and Western Ontario and McMaster Universities (WOMAC) OA index were performed at baseline and at study weeks 2, 4, 6, and 10. Net treatment effects were estimated by comparing outcomes between active and sham treatment study phases. RESULTS: Treatment benefits were noted for both of the trial's two pre-specified primary endpoints, VAS and WOMAC. VAS was reduced at all follow-up time points for patients receiving active treatment compared to sham treatment with a net treatment effect of 14.4+/-4.1 mm (P=0.001). Similarly, the WOMAC score was reduced significantly with active treatment at all measured points with a net effect of 8.8+/-1.9 points (P<0.001). The secondary endpoints, range of motion (ROM) and treatment satisfaction, also improved with active vs sham treatment. CONCLUSION: Four weeks treatment with combined CPM, vibration and local heating significantly decreases pain, improves ROM and the quality of life in patients with OA-K (ClinicalTrials.gov registration number: NCT00858416).

The relative contribution of the medial and lateral femoral circumflex arteries to the vascularity of the head and neck of the femur: a quantitative MRI-based assessment.

AIMS: We aimed to quantify the relative contributions of the medial femoral circumflex artery (MFCA) and lateral femoral circumflex artery (LFCA) to the arterial supply of the head and neck of the femur. MATERIALS AND METHODS: We acquired ten cadaveric pelvises. In each of these, one hip was randomly assigned as experimental and the other as a matched control. The MFCA and LFCA were cannulated bilaterally. The hips were designated LFCA-experimental or MFCA-experimental and underwent quantitative MRI using a 2 mm slice thickness before and after injection of MRI-contrast diluted 3:1 with saline (15 ml Gd-DTPA) into either the LFCA or MFCA. The contralateral control hips had 15 ml of contrast solution injected into the root of each artery. Next, the MFCA and LFCA were injected with a mixture of polyurethane and barium sulfate (33%) and their extra-and intra-arterial course identified by CT imaging and dissection. RESULTS: The MFCA made a greater contribution than the LFCA to the vascularity of the femoral head (MFCA 82%, LFCA 18%) and neck (MFCA 67%, LFCA 33%). However, the LFCA supplied 48% of the anteroinferior femoral neck overall. CONCLUSION: This study clearly shows that the MFCA is the major arterial supply to the femoral head and neck. Despite this, the LFCA supplies almost half the anteroinferior aspect of the femoral neck. Cite this article: Bone Joint J 2016;98-B:1582-8.

The terminal branches of the medial femoral circumflex artery: the arterial supply of the femoral head.

This study investigates and defines the topographic anatomy of the medial femoral circumflex artery (MFCA) terminal branches supplying the femoral head (FH). Gross dissection of 14 fresh-frozen cadaveric hips was undertaken to determine the extra and intracapsular course of the MFCA's terminal branches. A constant branch arising from the transverse MFCA (inferior retinacular artery; IRA) penetrates the capsule at the level of the anteroinferior neck, then courses obliquely within the fibrous prolongation of the capsule wall (inferior retinacula of Weitbrecht), elevated from the neck, to the posteroinferior femoral head-neck junction. This vessel has a mean of five (three to nine) terminal branches, of which the majority penetrate posteriorly. Branches from the ascending MFCA entered the femoral capsular attachment posteriorly, running deep to the synovium, through the neck, and terminating in two branches. The deep MFCA penetrates the posterosuperior femoral capsular. Once intracapsular, it divides into a mean of six (four to nine) terminal branches running deep to the synovium, within the superior retinacula of Weitbrecht of which 80% are posterior. Our study defines the exact anatomical location of the vessels, arising from the MFCA and supplying the FH. The IRA is in an elevated position from the femoral neck and may be protected from injury during fracture of the femoral neck. We present vascular 'danger zones' that may help avoid iatrogenic vascular injury during surgical interventions about the hip.

BMP signaling components are expressed in human fracture callus.

Of the various growth factors involved in the healing response after a fracture, bone morphogenetic proteins (BMPs) are emerging as key modulators. BMPs exert their effects by binding to a complex of type I and type II receptors leading to the phosphorylation of specific downstream effector proteins called Smads. The current study examined the presence of BMP signaling components in human callus obtained from five nascent malunions undergoing fracture fixation. These callus samples represented various stages of bone healing and a mixture of endochondral and intramembraneous bone healing. We performed immunohistochemistry on the callus, using antibodies for BMP (BMP-2,-3,-4,-7), their receptors (BMPR-IA, -IB, -II), and phosphorylated BMP receptor-regulated Smads (pBMP-R-Smads). Active osteoblasts showed fairly consistent positive staining for all BMPs that were examined, with the immunoreactivity most intense for BMP-7 and BMP-3. Immunostaining for BMPs in osteoblasts appeared to colocalize with the expression of BMPR-IA, -IB, and -II. Positive immunostaining for pBMP-R-Smads suggests that the BMP receptors expressed in these cells are activated. Staining for BMPs in cartilage cells was variable. The immunostaining appeared stronger in more mature cells, whereas staining for BMP receptors in cartilage cells was less ubiquitous. However, the expression of pBMP-R-Smads in cartilage cells suggests active signal transduction. Fibroblast-like cells also had a variable staining pattern. Overall, our findings indicate the presence of BMPs, their various receptors, and activated forms of receptor-regulated Smads in human fracture callus. To the best of our knowledge, this is the first study that documents the expression of these proteins in human fracture tissue. Complete elucidation of the roles of BMP in bone formation will hopefully lead to improved fracture healing care.

Indirect reduction and tension-band plating of tibial non-union with deformity.

Thirty-three patients who had a maligned non-union of the tibial diaphysis were treated by limited open exposure, indirect reduction with a femoral distractor, tension-band plating, lag-screw fixation, and autogenous bone-grafting. The time from the injury to treatment of the non-union averaged twenty-nine months. Twenty-two of the fractures were originally open and sixteen fractures had had a previous infection before treatment of the non-union. The non-unions were classified as hypertrophic in eight patients, oligotrophic in eighteen, and atrophic in seven. All had severe deformity, or the nature or level of the non-union, or both, precluded intramedullary nailing as a treatment option. All thirty-three non-unions healed at an average of four months; the average length of follow-up was nineteen months. The deformity was corrected, within acceptable limits, in thirty-two of the patients. Full motion of the knee was achieved in twenty-nine patients and of the ankle, in eighteen. Complications included four instances of superficial skin breakdowns, one deep infection, and one fracture of the plate. For non-unions of the tibial diaphysis with deformity that are not amenable to intramedullary nailing, the techniques of limited exposure, indirect reduction, tension-band plating, and bone-grafting can yield excellent anatomical and functional results.

Magnetic resonance venography to evaluate the deep venous system of the pelvis in patients who have an acetabular fracture.

We performed a prospective, blinded study to assess and compare the values of preoperative contrast venography and magnetic resonance venography in the detection of deep venous thrombosis in the thigh and pelvis of forty-five consecutive patients who had a displaced acetabular fracture. The magnetic resonance venography and contrast venography were performed an average of seven days (range, one to twenty-nine days) after the injury. Twenty-four asymptomatic thrombi were identified with magnetic resonance venography in fifteen (33 percent) of the patients. Four of the thrombi were in the superficial femoral vein, nine were in the common femoral vein, one was in the external iliac vein, seven were in the internal iliac vein, and three were in the common iliac vein. Ten (42 percent) of the twenty-four thrombi were confirmed with contrast venography; nine of them were located in the thigh. The remaining fourteen thrombi (58 percent) that had been noted on magnetic resonance venography could not be seen with contrast venography because they were located either in the deep pelvic veins or in the uninjured extremity. The thrombi in the internal iliac vein were identified only with magnetic resonance venography. Twelve of the fifteen patients who had thrombi had a filter placed in the inferior vena cava preoperatively. In eight of these patients, the filter was placed because of the findings of magnetic resonance venography alone. Magnetic resonance venography resulted in a change in the therapeutic management of ten (22 per cent) of the forty-five patients. There were no pulmonary emboli. We concluded that magnetic resonance venography is superior to contrast venography for the preoperative evaluation of proximal deep venous thrombosis in patients who have an acetabular fracture. Magnetic resonance venography is non-invasive, does not require the use of contrast medium, images the proximal aspects of both lower extremities simultaneously, and, most importantly, allows for the identification of deep venous thrombosis in the pelvis.

Stabilization of acetabular fractures in elderly patients.

Eighteen patients who were sixty years or older and had an acute displaced fracture of the acetabulum were managed with open reduction and internal fixation. The average age of the patients was sixty-seven years (range, sixty to eighty-one years). Nine fractures were a result of a motor-vehicle accident, and nine occurred in a fall. Nine patients had multiple associated injuries, and most (sixteen patients) had other complex acetabular fractures. All of the patients had open reduction and internal fixation with either the ilioinguinal approach (thirteen patients) or the Kocher-Langenbeck approach (five patients). All patients were managed postoperatively with early mobilization and physical therapy. All fractures united, and only one patient had a partial loss of reduction. Four patients who had a concentric reduction had a gap of as much as three millimeters in the articular surface due to comminution of the fracture. The complications included two pulmonary emboli, which resolved with anticoagulation, and one undetected intra-articular fragment, which led to an additional operation. No infections or iatrogenic nerve injuries were noted. Seventeen of the eighteen patients were followed for at least two years (average, thirty-one months). These patients had an average Harris hip-score of 90 points postoperatively. The treatment was regarded as having failed in only one patient. Open reduction and internal fixation of selected displaced acetabular fractures in the elderly can yield good results and may obviate the need for early and often difficult total hip arthroplasty.

Ballistics and gunshot wounds: effects on musculoskeletal tissues.

As a result of the increasing number of weapons in this country, as many as 500,000 missile wounds occur annually, resulting in 50,000 deaths, significant morbidity, and striking socioeconomic costs. Wounds are generally classified as low-velocity (less than 2,000 ft/sec) or high-velocity (more than 2,000 ft/sec). However, these terms can be misleading; more important than velocity is the efficiency of energy transfer, which is dependent on the physical characteristics of the projectile, as well as kinetic energy, stability, entrance profile and path traveled through the body, and the biologic characteristics of the tissues injured. Although bullets are not sterilized on discharge, most low-velocity gunshot wounds can be safely treated nonoperatively with local wound care and outpatient management. Typically, associated fractures are treated according to accepted protocols for each area of injury. Treatment of low-velocity, low-energy fractures is generally dictated by the osseous injuries, as these are similar in many regards to closed fractures. Soft tissues play a more critical role in high-velocity and shotgun fractures, which are essentially open injuries. Aside from perioperative prophylaxis, antibiotics are probably required only for grossly contaminated wounds; however, because contamination is not always apparent, most authors still recommend routine prophylaxis. High-energy injuries and grossly contaminated wounds mandate aggressive irrigation and debridement, including a thorough search for foreign material. Open fracture protocols including external fixation or intramedullary nailing and intravenous antibiotic therapy for 48 to 72 hours should be instituted. If there is vascular damage, exploration and repair are best performed after prompt fracture stabilization. Evaluation of the "four Cs"-color, consistency, contractility, and capacity to bleed-provides valuable information regarding the viability of muscle. Skin grafting is preferable when tension is required for wound closure, although other soft-tissue procedures, such as use of local rotation flaps or free tissue transfer, may be necessary, especially for shotgun wounds. Distal neurologic deficit alone is not an indication for exploration, as it often resolves without surgical intervention.

Practical management of venous thromboembolism following pelvic fractures.

The management of thromboembolic complications remains one of the most controversial issues in the care of patients with pelvic and acetabular fractures. Recent studies have indicated that the incidence of proximal deep vein thrombosis is much higher than was previously believed. These patients should be managed with a formal institutional protocol that includes universal prophylaxis, supplemented in some cases by screening for deep vein thrombosis.

Internal fixation of the distal humerus: a biomechanical comparison of methods.

Three commonly used configurations of various implants used for fixation of distal humeral fractures were quantitatively compared. The double plate construct, irrespective of plate type (1/3 tubular and/or 3.5 mm reconstruction plate), was significantly stronger, both in rigidity and fatigue testing, than cross screws or the single "Y" plate. If rigid stabilization of supracondylar or bicondylar distal humeral fractures is desired, then two plate constructs, at right angles (the ulna plate medially, the lateral plate posteriorly), are biomechanically optimal.

Bladder incarceration in a traumatic symphysis pubis diastasis treated with external fixation: a case report and review of the literature.

Fractures of the pelvis constitute a small but significant proportion of skeletal injuries. However, they are associated with significant morbidity and mortality, including damage to the urogenital system, especially the urethra and urinary bladder. We report the rare finding of bladder herniation and entrapment after reduction of a traumatic symphyseal diastasis by external fixation and the diagnosis of these injuries with computed tomography. A comprehensive review of the literature is also performed, to improve understanding and provide guidelines for evaluation and treatment of pelvic injuries with suspected bladder involvement.

The crescent fracture: a posterior fracture dislocation of the sacroiliac joint.

Between October 1987 and August 1992, 22 patients with crescent fractures, a posterior fracture-dislocation of the sacroiliac joint, were admitted, treated, and available for review at Tampa General Hospital and The Hospital for Special Surgery. The purpose of the study was twofold: (a) to evaluate the incidence, severity, and pattern of associated injuries, and (b) to determine the efficacy of a treatment protocol using a posterior extrapelvic approach and extraarticular internal fixation. The study population was composed of 13 females and nine males; the average age was 25 years (range 10-52). Despite the fracture pattern resulting in a rotationally unstable hemipelvis, all patients were hemodynamically stable at the time of presentation. Fourteen patients (64%) had other associated injuries, including five (23%) with closed head injury. In all cases a posterior extrapelvic approach was used with an anatomic reduction of the fractured iliac wing and the sacroiliac joint dislocation. Stable extraarticular internal fixation was obtained using intertable lag screws and outer-table neutralization plates. All the fractures were clinically and radiographically healed within 8-10 weeks postoperatively, and there were no acute wound, neurologic, or vascular complications. One patient developed osteomyelitis of the iliac crest 6 months postoperatively.

Somatosensory evoked potential monitoring in the surgical management of acute acetabular fractures.

Fifty patients undergoing acute acetabular fracture surgery had intraoperative somatosensory evoked potential (SSEP) monitoring. Group II, the final 38 patients, in addition had independent neurological evaluation preoperatively and postoperatively. Thirteen of 50 patients (26%) had preoperative sciatic nerve involvement. Fourteen of 50 patients (28%) developed significant intraoperative SSEP changes (decreased amplitude, increased latency). When the nerve was involved preoperatively (high-risk group), changes in SSEP occurred in 60% of patients. Iatrogenic sciatic/peroneal neuropraxia occurred in only one patient in the series (2%), and this resolved within 4 months. These results compare favorably to the incidence of 5-18% reported in the literature. We conclude SSEP is feasible and should be used in the operative treatment of acetabular fractures, especially the posterior fracture patterns and for those in the high-risk group.

Anteroinferior plating of midshaft clavicular nonunions.

Many different techniques have been reported for the treatment of clavicular nonunions. Those techniques involving screws and plate generally position the plate on the superior (subcutaneous) surface of the clavicle. To decrease the risk of screw pull-out and prominence of the instrumentation, we currently perform anteroinferior plating using a 3.5-millimeter pelvic reconstruction plate with a lag screw and bone graft. A consecutive group of twelve patients with midshaft clavicular nonunions was treated with this technique. All nonunions united after an average of 3.6 months (range 2 to 8 months). All patients regained full function and mobility of the shoulder. The technique as described in this article illustrates a successful modification of the traditional plating technique of midshaft clavicular nonunions. We conclude that anteroinferior plating is a reliable and safe technique that leads to high rates of bony union in midshaft clavicular nonunions.

Effect of impact load on articular cartilage: development of an intra-articular fracture model.

OBJECTIVES: To investigate the biological and mechanical effects of a single-impact load on articular cartilage. DESIGN: An in vitro laboratory study was performed using mature bovine cartilage and bone, and isolated cartilage explants. Each specimen was impacted with a single load applied with a specially designed impactor and materials test machine. Chondrocyte metabolic activity and cartilage structural integrity was investigated using force displacement curves, radionuclide labeling, histology, and changes in water content. SETTING: Laboratory for Soft Tissue Research, New York, New York, U.S.A. SPECIMENS: Viable mature bovine cartilage and cartilage and bone explants. MAIN OUTCOME MEASUREMENTS: Mechanical failure, proteoglycan synthesis, water content, histology, radiography, and scanning electron microscopy changes occurring during the twenty-four-hour period immediately following impact. RESULTS: Force/displacement curves for the cartilage and bone explants demonstrated two failure-stress peaks, the first at fifty megapascals, representing cartilage failure, and a second peak at seventy-five megapascals, representing bone failure. Fine grain radiographs, histology, and scanning electron microscopy all confirmed the destruction of the cartilage in the area of direct impact (zone I) and subchondral bone failure and the detachment of the cartilage within the lesser impacted area (zone II). Proteoglycan synthesis was reduced significantly (p < 0.05) in the areas of direct impact (zone I) compared with areas with less or no impact (zones II and III, respectively). Significantly greater water content (p < 0.05) was found within the cartilage of zone I compared with zones II and III. CONCLUSIONS: Significant and possibly irreversible articular cartilage damage occurs after a single high-energy impact load.

The detection and management of proximal deep venous thrombosis in patients with acute acetabular fractures: a follow-up report.

OBJECTIVE: To determine the efficacy of a thromboprophylaxis protocol that included deep venous thrombosis (DVT) prophylaxis (subcutaneous heparin), preoperative screening with magnetic resonance venography (MRV), and therapeutic management (vena caval interruption preoperatively, therapeutic heparin anticoagulation postoperatively) when indicated. DESIGN: Prospective, consecutive. SETTING: Tertiary referral, teaching hospital in New York City. PATIENTS: One hundred one patients with acutely displaced acetabular fractures. MAIN OUTCOME MEASURE: Preoperative MRV was performed to assess vascular structures. Patients with proximal DVT received vena caval filter interruption preoperatively and therapeutic warfarin postoperatively. Patients without proximal DVT received only subcutaneous heparin preoperatively and low-dose warfarin postoperatively. RESULTS: Forty-nine asymptomatic thrombi were identified in thirty-four of 101 patients (34 percent). Location of thrombi were in the popliteal vein in four of forty-nine patients (8 percent), superficial femoral vein in eight of forty-nine (16 percent), common femoral vein in thirteen of forty-nine (27 percent), external iliac vein in six of forty-nine (12 percent), internal iliac vein in fourteen of forty-nine (29 percent), and common iliac vein in four of forty-nine (8 percent). Thrombi were isolated to the injured extremity in twenty-six of thirty-four patients (76 percent), bilateral in four of thirty-four (12 percent), and isolated to the uninjured extremity in four of thirty-four (12 percent). Twenty-six of the thirty-four patients with proximal thrombi received preoperative vena caval filters. As a result of this protocol, only one patient (1 percent) developed a nonfatal pulmonary embolism. CONCLUSION: MRV is a sensitive screening examination that allows the placement of inferior vena caval filters based on documented proximal thrombosis. We anticipate that preoperative DVT screening with MRV will significantly decrease the incidence of fatal pulmonary embolism in this high-risk population.

Retrograde reamed femoral nailing.

Closed, reamed, antegrade nailing remains the standard of care for femoral shaft fractures. This technique however, may be less attractive in the management of femoral shaft fractures associated with (a) ipsilateral acetabular, pelvis, or femoral neck fractures; (b) polytrauma requiring multiple simultaneous surgical procedures; and (c) pregnancy. We now report on our experience with the retrograde femoral nailing as a treatment option in these situations. Between 4/88 and 10/90, 29 retrograde femoral nailing in 24 patients were attempted. Average age was 29.3 (16-74) years. Five fractures were open. Fracture location was isthmal in 14 and infraisthmal in 15. The comminution was classified according to Winquist and Hansen: I(10), II(7), III(7), and IV(5). Nailing was possible in 28/29 cases. Insertion was made through an extraarticular medial condylar portal. Nail diameter ranged from 10 to 13 mm. An AO Universal Femoral Nail was used in the first 11 cases; all subsequent fractures were stabilized using an AO Universal Tibial Nail because its design appeared better suited to this technique. Follow-up was possible for 25 fractures in 21 patients and averaged 16.0 (range, 11-27); months 23/25 (92%) fractures healed within 12 weeks. No case was associated with an infection, loss of reduction, or nail failure. Knee flexion averaged 122 degrees; only two knees had an extensor lag of > 5 degrees. Intraoperative complications included three cases of crack propagation at the insertion site, and four infraisthmal malreductions (two valgus, two flexion). Based on these results, we feel that retrograde reamed femoral nailing is a suitable alternative to antegrade nailing and should be considered in situations where proximal access is neither possible nor desirable.

Intraoperative somatosensory evoked potential monitoring during acute pelvic fracture surgery.

Independent clinical neurological evaluation and intraoperative somatosensory evoked potential (SSEP) monitoring was performed on 30 vertically unstable hemipelvis fractures in 28 patients undergoing acute open reduction and internal fixation. Preoperative ipsilateral neurologic injury of the sciatic/lumbosacral plexus was noted in 15 of 30 fractures (50%). Significant unilateral SSEP changes occurred during manipulative reduction of two displaced sacroiliac joints and one sacral fracture. Because of the expeditious response of the surgical team, with release of traction/retraction, SSEP returned to baseline and no patient sustained an iatrogenic nerve injury or worsening of their preoperatie neurologic status. The incidence of postinjury lumbosacral plexopathy in unstable pelvic fractures is high (50%) when careful preoperative evaluation including SSEP is performed. The use of intraoperative SSEP monitoring is feasible in acute posterior pelvic fracture surgery and can help identify potential intraoperative iatrogenic lumbosacral neurological compromise.

Anterior iliac crest bone graft harvesting using the corticocancellous reamer system.

OBJECTIVE: To evaluate the anterior iliac crest bone graft harvesting procedure using a corticocancellous acetabular reamer system. DESIGN: A total of 390 bone grafting procedures were reviewed using retrospective chart review. Two hundred twenty procedures were performed using the reamer system, and 170 were performed using traditional techniques (cortical strip, tricortical wedge, and cancellous trap door grafts). SETTING: The Hospital for Special Surgery, New York, New York. PARTICIPANTS: Operative cases involving an anterior iliac crest bone graft procedure between January 1, 1991 and February 28, 1998. MAIN OUTCOME MEASUREMENTS: Complications were organized by the categories major, intermediate, and minor. Statistical analysis included assessment of comorbidity to determine risk factors that may be associated with a propensity for complications. RESULTS: Of the 390 patients reviewed, 13.1 percent (51 of 390) developed a total of seventy-one complications. Of the seventy-one complications, forty were reamer-associated and thirty-one were traditional method-associated complications. As compared with the traditional group, major morbidity was lower in the reamer group (0.9 percent [2 of 220] as compared with 1.8 percent [3 of 170] [ p = 0.4]). Intermediate and minor morbidity were slightly higher in the reamer group than in the traditional group (5.9 percent [13 of 220] as compared with 5.3 percent [9 of 170] [ p = 0.7] and 9.5 percent [21 of 220] as compared with 7.1 percent [12 of 170] [ p = 0.4], respectively). Of the forty reamer-associated complications, 90 percent (36 of 40) resolved within ninety days (average 36.6 days). Of the thirty-one traditional method-associated complications, 74.2 percent (23 of 31) were resolved by 90 days (average 50.6 days). Using logistical regression analysis obesity (body mass index) ( p = 0.03) and smoking ( p = 0.03) were correlated with development of a complication. Furthermore, if a patient was obese and a smoker, the analysis predicted an 83 percent chance of developing a complication. CONCLUSIONS: The reamer technique was found to be safe and efficacious while producing a large amount of autogenous corticocancellous bone graft. Overall complication rates for the reamer and the traditional groups were comparable. The corticocancellous reamer system represents an effective option for bone graft harvesting.

Outer gloves in orthopaedic procedures: a polyester/stainless steel wire weave glove liner compared with latex.

OBJECTIVE: To compare the efficacy of traditional double latex gloving with that of a highly cut-resistant polyester/stainless steel wire weave glove (PSSWWG) over a single latex inner glove for the prevention of perforation of the inner latex glove. DESIGN: The primary surgeon and first assistant were involved in a prospective randomized study. Group I consisted of twenty-five procedures in which double latex gloves were used. Group II consisted of twenty-five procedures in which a PSSWWG liner was worn over an inner latex glove. All inner gloves were tested for perforations; all gloves exchanged that were presumed to have a perforation were noted and also tested. The type and length of the procedure were recorded. The dominant hand was recorded for all participants, along with their comments on the PSSWWG liner's performance. SETTING: Orthopaedic Trauma Service, Hospital for Special Surgery. New York. PATIENTS/PARTICIPANTS: Major operative cases, November 1996 to February 1997. MAIN OUTCOME MEASUREMENTS: Inner latex glove perforations. RESULTS: With the use of PSSWWG liners, the percentage of inner gloves found with a perforation dropped from 19 percent in the double latex group to 15 percent in the PSSWWG liner group (not statistically significant, p = 0.4). Two thirds of the perforations were in the primary surgeon's gloves, located in either the index finger or thumb. Nearly 80 percent of all perforations went unrecognized in both groups. Ninety-five percent of all perforations were in gloves that had been in use for more than 120 minutes (statistically significant, p = 0.01). CONCLUSIONS: The particular cut-resistant glove studied (Sceptor) did not significantly reduce the rate of inner glove perforations. Other studies with different cut-resistant glove types and protocols have proven the liners effective. We would still recommend using outer cloth or cut-resistant type gloves when bone fragments are being manipulated or when using sharp implants or saws. At a minimum, surgical gloves should be changed every two hours.