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Nirmal Tejwani

Publications and source records attributed to Nirmal Tejwani.

15 recordsLinked to original sources
PubMed2006

Helical blade versus sliding hip screw for treatment of unstable intertrochanteric hip fractures: a biomechanical evaluation.

OBJECTIVE: To compare the fixation stability in the femoral head with sliding hip screw versus helical blade designs for unstable, intertrochanteric hip fractures. METHODS: A simulated, unstable intertrochanteric hip fracture was created in six pairs of cadaveric femurs. One of each pair was treated using an intramedullary nail with a sliding hip screw (ITST) for femoral head fixation and the other was treated with a nail with a helical blade (TFN). Each specimen was cyclically loaded with 750N vertical loads applied for 10, 100, 1000 and 10,000 cycles. Measurements for femoral head displacement, fracture fragment opening and sliding were made. Specimens were then loaded to failure. RESULTS: There was significantly more permanent inferior femoral head displacement in the ITST samples compared to the TFN samples after each cyclic loading (all p values<0.05). There was significantly more permanent fracture site opening and inferior displacement in the ITST group compared with the TFN group at 1000 and 10,000 cycles (p<0.05). Final loads to failure were not significantly different (p=0.51) between the two treatment groups. Nine specimens demonstrated fracture extension into the anteromedial cortex and subtrochanteric region and three specimens, which had an ITST implant, demonstrated a splitting fracture of the femoral head. CONCLUSION: This study demonstrated that fixation of the femoral head with a helical blade was biomechanically superior to fixation with a standard sliding hip screw in a cadaveric, unstable intertrochanteric hip fracture model.

Biomechanical Phenomena↗
PubMed2006

Preoperative assessment of tibial nail length: accuracy using digital radiography.

This study was performed to determine if picture archiving communication systems can provide a more accurate method of determining implant length for intramedullary tibial nailing. Postoperative radiographs of 40 patients who underwent intramedullary nailing of their tibial shaft fractures using picture archiving communication systems were retrieved. In phase one and two of this investigation, tibial nail lengths were measured using "measuring distance" and "measure calibration" tools displayed on the respective digital systems. Phase 3 of this study involved 5 tibial Sawbones (Pacific Research Laboratories, Vashon, Wash) radiographically captured on the picture archiving communication systems with a radiograph marker of known length. Using the "measuring distance" and "measure calibration" tools in phases one and two did not result in accurate measurements. Of 40 digital radiographic images measured and calibrated with the on-screen ruler and using the digital system tools, 100% of our measurements were inaccurate. An average of 19.4-mm and 10.6-mm difference was noted in uncorrected measurements on anteroposterior (AP) and lateral views, respectively. An average 25.8 mm and 15.7 mm was noted in calibrated (corrected) measurements on AP and lateral views respectively. Digitally measured and calibrated lengths were an average 22 mm and 25 mm greater from the actual known length of the tibial nail, respectively. Phase 3 of our study presented the most accurate results in length determination of tibial nail length.

Body Weights and Measures↗
PubMed2005

What's new in hip fractures? Current concepts.

Hip fractures have been among the most studied injury patterns in adults. The number of hip fractures is increasing exponentially, and their treatment costs place great economic strain on society. Recently developed hip fracture treatments, emphasizing cost containment, deformity prevention, and evidence-based medicine, are attempts to optimize patient outcomes. In this article, we outline some of these developments with respect to femoral neck and intertrochanteric fractures.

Bone Screws↗
PubMed2004

Knee laxity associated with a proximal diaphyseal tibial and fibular fracture.

If operative treatment of a proximal diaphyseal tibial and fibular fracture is required, in most cases, it involves reduction and stabilization of only the tibial fracture. In this case report, after stabilization of the tibial fracture with an intramedullary nail, the patient continued to demonstrate significant varus knee laxity, despite an intact proximal tibiofibular joint and undisplaced fibular head. The stability of the knee was achieved only with internal fixation of the segmental fibular fracture. This case shows the importance of assessing knee laxity in all cases of proximal tibial and fibular fractures.

Adult↗
PubMed2004

Can external fixation maintain reduction after distal radius fractures?

BACKGROUND: The purpose of this study was to assess the effectiveness of external fixation and percutaneous pinning in maintaining distal radius fracture reduction over a 6-month period and to identify factors that might predict loss of fracture reduction. METHODS: Seventy cases had complete radiographic evaluation before surgery; at surgery; and at 6-week, 3-month, and 6-month follow-up. Radiographic parameters measured included volar tilt, dorsal displacement, radial inclination, radial height, radial shift, and ulnar variance. RESULTS: Dorsal tilt averaged 17.5 degrees from neutral before surgery; this value was corrected to 0.9 degree at surgery, but then progressed to 4.2 degrees by the 6-month follow-up. At 6-month follow-up, 49% of cases had lost more than 5 degrees of initially reduced volar tilt. However, none of these patients went from an acceptable initial reduction to an unacceptable reduction at 6 months. Initial deformity, patient age, use of bone graft, and duration of external fixation were not predictors of loss of reduction. CONCLUSION: Loss of reduction of volar tilt was seen for a period of up to 6 months after fixation, despite the use of pinning to hold the reduction. No specific predictor of loss of reduction was noted, although there was a trend toward loss of reduction in younger patients.

Adult↗
PubMed2003

Heterotopic ossification after knee dislocation: the predictive value of the injury severity score.

OBJECTIVE: To determine the relationship of multiple variables, including the Injury Severity Score (ISS), closed head injury (CHI), and timing and type of surgery to formation of motion-limiting heterotopic ossification (HO) following knee dislocation. DESIGN: Longitudinal observational study. SETTING: University level 1 trauma center. PATIENTS/PARTICIPANTS: Thirty-five consecutive patients with 36 knee dislocations (OTA fracture and dislocation classification 40-D) admitted over a 26-month period. MAIN OUTCOME MEASUREMENTS: Admission ISS, Glasgow Coma scale (GCS) scores, CHI, timing (> or < 3 weeks from injury) and type (open or arthroscopic) of surgery, number of cruciate ligaments reconstructed, medial surgical procedure, and eventual presence or absence of motion-limiting HO. RESULTS: A classification system for HO was developed ranging from none (type 0) to ankylosing (type IV) HO. Twenty-nine patients with type 0-III HO recovered an average range of motion of 126 degrees at an average of 14 months (group A). Six patients formed ankylosing type IV HO (group B). The ISS in group A ranged from 9 to 26. ISS in group B ranged from 26 to 50 (P < 0.001). Regarding the formation of type IV HO, the sensitivity of an ISS >/=26 was 100%, the specificity was 97%, and the positive predictive value was 86%. Patients in group B had a greater incidence of documented CHI (P < 0.025). Timing and type of surgery, number of ligaments reconstructed, and whether or not the patient had a medial surgical procedure had no statistical influence on degree of HO formation. CONCLUSIONS: An ISS of 26 seems to be a discrete boundary above which patients with knee dislocation are at extremely high risk for type IV HO formation if undergoing surgical reconstruction and below which patients are likely spared this complication. The presence of a CHI is a significant factor in type IV HO formation, although harder to quantify. None of the remaining independent variables studied were significantly related to ankylosing type IV HO formation.

Anterior Cruciate Ligament Injuries↗
PubMed2003

Review: acute compartment syndrome of the foot.

Foot compartment syndrome is a serious potential complication of foot crush injury, fractures, surgery, and vascular injury. The purpose of this article is to summarize and review the existing literature on this entity. Long-term sequelae of foot compartment syndrome (FCS) include contractures, deformity, weakness, paralysis, and sensory neuropathy. These complications are poorly tolerated, and often necessitate multiple procedures for rehabilitation. Therefore, the threshold for considering compartment syndrome and performing fasciotomy must be low to minimize such outcomes. The existence of nine foot compartments and frequent presence of complicating injuries necessitate multi-stick needle catheterization for direct measurement of compartment pressures. Fasciotomy is indicated when compartment pressure exceeds 30 mmHg, or if compartment pressure is greater than 10-30 mmHg below diastolic pressure. The approaches for compartment decompression generally include two dorsal incisions for access to forefoot compartments, and one medial incision for decompression of the calcaneal, medial, superficial, and lateral compartments.

Acute Disease↗
PubMed2002

Isolated gastrocnemius tightness.

BACKGROUND: Contracture of the gastrocnemius-soleus complex has well-documented deleterious effects on lower-limb function in spastic or neurologically impaired individuals. There is scarce literature, however, on the existence of isolated gastrocnemius contracture or its impact in otherwise normal patients. We hypothesized that an inability to dorsiflex the ankle due to equinus contracture leads to increased pain in the forefoot and/or midfoot and therefore a population with such pain will have less maximum ankle dorsiflexion than controls. We further postulated that the difference would be present whether the knee was extended or flexed. METHODS: This investigation was a prospective comparison of maximal ankle dorsiflexion, as a proxy for gastrocnemius tension, in response to a load applied to the undersurface of the foot in two healthy age, weight, and sex-matched groups. The patient group comprised thirty-four consecutive patients with a diagnosis of metatarsalgia or related midfoot and/or forefoot symptoms. The control group consisted of thirty-four individuals without foot or ankle symptoms. The participants were clinically examined for gastrocnemius and soleus contracture and were subsequently assessed for tightness with use of a specially designed electrogoniometer. Measurements were made both with the knee extended (the gastrocnemius under tension) and with the knee flexed (the gastrocnemius relaxed). RESULTS: With the knee fully extended, the average maximal ankle dorsiflexion was 4.5 degrees in the patient group and 13.1 degrees in the control group (p < 0.001). With the knee flexed 90 degrees, the average was 17.9 degrees in the patient group and 22.3 degrees in the control population (p = 0.09). When gastrocnemius contracture was defined as dorsiflexion of < or = 5 degrees during knee extension, it was identified in 65% of the patients compared with 24% of the control population. However, when gastrocnemius contracture was defined as dorsiflexion of < or = 10 degrees, it was present in 88% and 44%, respectively. When gastrocnemius-soleus contracture was defined as dorsiflexion of < or = 10 degrees with the knee in 90 degrees of flexion, it was identified in 29% of the patient group and 15% of the control group. CONCLUSIONS: On the average, patients with forefoot and/or midfoot symptoms had less maximum ankle dorsiflexion with the knee extended than did a control population without foot or ankle symptoms. When the knee was flexed 90 degrees to relax the gastrocnemius, this difference was no longer present. CLINICAL RELEVANCE: These findings support the existence of isolated gastrocnemius contracture in the development of forefoot and/or midfoot pathology in otherwise healthy people. These data may have implications for preventative and therapeutic care of patients with chronic foot problems.

Adult↗
PubMed2002

Gunshot wounds to the lower extremities.

In this article, we briefly mention the personal, social, and economic costs of gunshot injuries; describe the science of ballistics and how differences in ballistics affect gunshot wounds and their treatment; and review the general principles involved in managing gunshot injuries. We will summarize the strategies for treating adults with gunshot injuries to specific regions of the lower extremities--the hip, the femur, the knee, the tibia, and the foot.

Debridement↗
PubMedDate not supplied

Quadriceps tendon rupture.

Rupture of the quadriceps tendon is an uncommon yet serious injury requiring prompt diagnosis and early surgical management. It is more common in older (>40 years) individuals and sometimes is associated with underlying medical conditions. In particular, bilateral spontaneous rupture may be associated with gout, diabetes, or use of steroids. Clinical findings typically include the triad of acute pain, impaired knee extension, and a suprapatellar gap. Imaging studies are useful in confirming the diagnosis. Although incomplete tears may be managed nonsurgically, complete ruptures are best treated with early surgical repair.

Animals↗
PubMedDate not supplied

Biomechanical comparison of five external wrist fixators.

The relative stiffness of five different external wrist fixators currently in use for distal radius fractures was determined using a uniform fracture model consisting of wood dowels to isolate the effects of the fixators themselves. Each construct was loaded in axial compression, eccentric and cantilever modes of bending, and torsion. The stiffest of the fixators varied by a factor of three in compression, five in bending, and three in torsion. Although the ideal stiffness of a wrist fixator is unknown, there is a large variation in the stiffness of existing devices.

Biomechanical Phenomena↗