Simultaneous management of ipsilateral gonarthritis and ununited tibial stress fracture: combined total knee arthroplasty and internal fixation.

Nonunion of a proximal tibial stress fracture is rare and can be difficult to manage, especially if associated with ipsilateral gonarthritis. Three patients with nonunion of a proximal tibial stress fracture adjacent to an arthritic knee joint were managed by performing simultaneous total knee arthroplasty and internal fixation of the fracture site. The technique involved performing a total knee arthroplasty with angular correction at the site of the extra-articular and intra-articular deformity, bone grafting of the nonunion site, and stabilization of the fracture with a long uncemented intramedullary stemmed tibial component and a unicortical plate. Fibular ostectomy was required during the index surgery in 2 cases to achieve the desired angular correction. In all 3 patients, healing of the nonunion site and limb realignment was achieved. There were no complications or infections associated with the surgery. All patients progressed to full weight bearing at 3 months and had clinical and radiographic union of the nonunion site at 6 months.

Component size asymmetry in bilateral total knee arthroplasty.

A review of 268 consecutive patients undergoing bilateral total knee arthroplasty (TKA) was performed to determine whether component size asymmetry exists in patients undergoing bilateral TKAs. Component sizes were selected based on preoperative radiographic templating and intraoperative sizing measurements irrespective of the component sizes chosen for the other knee. All radiographs were evaluated according to described criteria. Component sizes used for the femur, tibia, and patella were compared between the right and left knees. Of the 268 bilateral TKAs, 18 (6.7%) femoral components varied in size between right and left knees. There were no statistical differences for patellar or tibial component size asymmetry or knee function pre- or postoperatively. Patients with asymmetrically sized femoral components had no statistical difference between left and right knees with respect to knee score, pain, function, range of motion, incidence of lateral release, or complications.

Analysis of routine histological evaluation of tissues removed during primary hip and knee arthroplasty.

BACKGROUND: It has often been hospital policy to send all resected specimens obtained during a total hip or knee arthroplasty for histological evaluation. This practice is expensive and may be unnecessary. We sought to determine the ability of surgeons to diagnose primary joint conditions correctly, and we attempted to identify any possible risks to the patient resulting from the omission of routine histological evaluation of specimens at the surgeon's discretion. Our objective was to ascertain whether routine histological evaluation could be safely omitted from the protocol for primary hip and knee arthroplasty without compromising the care of the patient. METHODS: A total of 1388 consecutive arthroplasties in 1136 patients were identified from a database of primary total hip and knee arthroplasties that was prospectively maintained by the senior one of us. Follow-up data obtained at a mean of 5.5 years (range, two to ten years) were available after 92 percent (1273) of the 1388 arthroplasties. The preoperative diagnosis was determined from the history, findings on clinical examination, and radiographs. The intraoperative diagnosis was determined by gross inspection of joint fluid, articular cartilage, synovial tissue, and the cut surfaces of resected specimens. The combination of the preoperative and intraoperative diagnoses was considered to be the surgeon's clinical diagnosis. All resected specimens were sent for routine histological evaluation, and a pathological diagnosis was made. Attention was given to whether a discrepancy between the surgeon's clinical diagnosis and the pathological diagnosis altered the management of the patient. The original diagnoses were updated with use of annual radiographs and clinical assessments. The cost of histological examination of specimens obtained at arthroplasty was determined by consultation with hospital administration, accounting, and pathology department personnel. RESULTS: A pathological fracture or an impending fracture was diagnosed preoperatively and confirmed intraoperatively during twelve of the 1388 arthroplasties. Histological analysis demonstrated malignancy in specimens obtained during eleven of these arthroplasties and evidence of a benign rheumatoid geode in the specimen obtained during the twelfth arthroplasty. The preoperative and intraoperative diagnoses made before and during the remaining 1376 arthroplasties were benign conditions, which were confirmed histologically in all patients. No diagnosis changed during the follow-up period. As demonstrated by a comparison with the histological diagnosis, the surgeon's clinical diagnosis of malignancy had a sensitivity of 100 percent (95 percent confidence interval, 74.0 to 100 percent), a specificity of 99.9 percent (95 percent confidence interval, 99.6 to 100 percent), a positive predictive value of 91.7 percent (95 percent confidence interval, 64.6 to 98.5 percent), and a negative predictive value of 100 percent (95 percent confidence interval, 99.7 to 100 percent). There was a discrepancy between the preoperative and intraoperative diagnoses associated with eleven arthroplasties. All eleven intraoperative diagnoses were correct, as confirmed histologically. Excluding the patients who had a pathological or impending fracture, the accuracy of the surgeon's preoperative diagnosis was 99.2 percent (95 percent confidence interval, 98.6 to 99.5 percent). When the intraoperative and preoperative diagnoses were combined, the accuracy was 100 percent (95 percent confidence interval, 99.7 to 100 percent). Histological evaluation at our hospital resulted in total charges, including hospital costs and professional fees, of $196.27 and a mean total reimbursement of $102.59 per evaluation. In our series of 1136 patients with 1388 arthroplasties, these costs could have been eliminated for all but the twelve patients who had a suspected malignant lesion and the one patient in whom pigmented villonodular synovitis was found. (ABSTRACT

Simultaneous ipsilateral revision total hip arthroplasty and revision total knee arthroplasty with entire femoral allograft.

Treatment of periprosthetic fractures of both total hip arthroplasty and total knee arthroplasty has been well described in the literature. Treatments used have included closed treatment, revision arthroplasty with or without bone graft, open reduction internal fixation with plating, or intramedullary fixation [1-4]. However, treatment of periprosthetic fractures that involve a femur that has both a proximal total hip prosthesis and a distal total knee prosthesis has not been thoroughly described in the literature. We present a persistent distal femoral nonunion of a periprosthetic fracture, which was treated by using an entire femoral allograft with simultaneous ipsilateral revision total hip arthroplasty and total knee arthroplasty.

Postoperative radiographs after total knee arthroplasty: a cost-containment strategy.

We reviewed a single surgeon's experience with 646 consecutive total knee arthroplasties (TKAs) performed over a 6-year period to determine whether routine in-hospital radiographs could be safely avoided. Five hundred fourteen patients underwent 589 primary and 57 revision TKAs. One hundred thirty-two patients had bilateral procedures. Radiographs were obtained during the index hospitalization for 12 (2%) knees and were ordered selectively to assess femoral notching > or =3 mm, concomitant osteotomy, bulk allograft reconstruction, stem extension relative to existing hardware or screw holes, or falls during the index hospitalization. Radiographs were delayed until the initial postoperative office visit for the remaining 634 (98%) knees. Six hundred seventeen of 646 knees (96%) were evaluated at a mean follow-up of 4.3 years (range: 2 to 8 years). No patient experienced any complication that was considered to be attributable to not obtaining earlier postoperative radiographs. Three patients experienced late fractures and 7 patients developed perioperative soft-tissue complications or infections. None of these cases were adversely affected by delaying the initial postoperative radiographs. Eliminating in-hospital radiographs with radiologist interpretation resulted in a potential savings of $246 in hospital charges, $198 in private insurance reimbursements, and $65 in hospital costs per TKA. These findings indicate that radiographs following TKA can be delayed in most cases until the first postoperative office visit without compromising patient care.

Isolated revision acetabuloplasty using a porous-coated cementless acetabular component without removal of a well-fixed femoral component. A 3- to 9-year follow-up study.

The results of isolated acetabular revision performed in 31 patients (32 hips) were monitored for between 3 and 9 years. All femoral components were well fixed and not removed or revised at the time of index surgery. There were 4 hips with little or no acetabular bony defect, 2 hips with pure segmental defects (type I), 10 hips with cavitary defects (type II), 15 with combined segmental cavitary defects (type III), and I with pelvic discontinuity (type IV). All revision acetabular implants were cementless, using a porous-coated hemispheric cup with or without bone-graft. There were four grade I reconstructions, 16 grade II reconstructions, and 12 grade III reconstructions. At final follow-up evaluation 94% of the cups were judged to be stable. Two hips required a second revision acetabuloplasty because of loss of fixation of the cup. The 2 repeat revisions were also done without removal of the femoral component. One acetabular component had evidence of rotational migration, which stabilized and remained nonprogressive. There were no cases of femoral component radiographic or clinical failure. The mean pre and postoperative hip scores were 44 and 83, respectively. The pre- and postoperative pain scores were 12 and 42, respectively. The findings of this study suggest that isolated acetabular revision, using a cementless porous-coated hemispheric cup, can be successfully performed without removing or revising a well-fixed femoral stem and not compromise the final outcome.

Hypercholesterolemia: an association with osteonecrosis of the femoral head.

To determine whether hypercholesterolemia is an associated factor for idiopathic avascular necrosis, serum cholesterol levels were measured in all patients presenting with idiopathic avascular necrosis of the femoral head from December 1987 to December 1995. Of 77 patients, with 114 affected hips, presenting with avascular necrosis of the femoral head, 58 patients, with 81 affected hips, were excluded for known associated risk factors. Of the remaining 19 patients (33 hips) who were diagnosed with idiopathic avascular necrosis, 16 had serum cholesterol levels that were statistically elevated (mean value, 254 mg/dL) compared with accepted age-matched control standards (P < 0.0031). Four of the 16 patients were taking cholesterol-lowering medications at the time of initial evaluation and testing. In addition, 12 of the 16 patients had bilateral avascular necrosis, suggesting that the systemic effect of hypercholesterolemia may be involved in the pathophysiology of osteonecrosis. These results suggest an association between elevated serum cholesterol levels and idiopathic avascular necrosis of the femoral head.

A modified direct lateral approach for primary and revision total hip arthroplasty. A prospective analysis of 453 cases.

A prospective analysis of 453 consecutive primary and revision total hip arthroplasties (THAs) were reviewed. The modified direct lateral approach was used in 306 of 319 (96%) primary THAs and 115 of 134 (86%) revision cases for a total of 421 of 453 (93%) procedures. There were three dislocations in the revision group of patients. All three patients had at least two previous arthroplasties prior to their index surgery and at the time of surgery were noted to have very poor tissue quality, making the repair difficult. There were no postoperative dislocations in the primary THA group, with an overall dislocation rate of 0.7%. The incidence of postoperative limp in the primary THA group was 18%. The overall incidence, including revision surgery, was 27%. The presence of a persistent limp after initial rehabilitation was dependent on the number of previous surgeries, leg-length discrepancy greater than 2.7 cm, revision THA requiring a proximal femoral allograft, and preexisting deformities. Limp was therefore believed not to be related to the use of the modified direct lateral approach.

Prospective analysis of uncemented and hybrid primary porous coated anatomic total hip arthroplasties in a community setting.

One hundred thirty-four consecutive primary total hip arthroplasties, with 100 uncemented and 34 hybrid cemented femoral components, were performed in 119 patients in a community hospital setting, and the patients were followed for between 2 and 4 years. Two-year followup mean Harris hip ratings were 88 for the hybrid group and 90 for the porous coated group. The pain score was 43 for both groups. The incidence of thigh pain was 9% at 1 year, 6% at 2 years, and 5% at 3 years in the porous coated group; none of the pain was disabling. A persistent limp was noted in 19% of patients: 18% of the porous coated group and 22% of the hybrid group. Limp was believed to be related to the number of prior hip surgeries, preoperative leg length discrepancy greater than 2.7 cm, and comorbid musculoskeletal diseases, and not to utilization of the modified direct lateral approach. Radiographic zonal analysis revealed that 99 of the porous coated femoral components had a stable implant fixation with bone ingrowth; one component was stabilized by fibrous ingrowth. The average femoral size used was two sizes larger than those used elsewhere, when the same prosthesis was used during the same time interval. These results obtained in a community hospital setting using either modern cemented or porous-coated insertion techniques are similar to those achieved in major medical centers.

The effect of halo-vest length on stability of the cervical spine. A study in normal subjects.

In order to study how the efficiency of the halo vest is affected by different lengths of the vest, an experimental headband was devised that allowed the head of a normal person to be held securely in the halo attachment. The vest was then modified to allow it to be adjusted to three different lengths (Fig. 2): a full vest extended to the iliac crests, a short vest extended to the twelfth ribs, and a half vest extended to the level of the nipples. Twenty normal, healthy adult men participated in the study. For each vest length, radiographs were made of each subject demonstrating rotation, flexion-extension, and lateral bending of the cervical spine. There was no rotation of the cervical spine, regardless of the length of the vest. There was a variable degree of motion in flexion or extension of the upper part of the cervical spine with all vest lengths, but this was not statistically significant. There was definite increase of motion caudad to the level of the fifth cervical vertebra regardless of the length of the vest. We concluded that a lesion of the upper part of the cervical spine can be treated effectively by halo traction with a half vest. This will improve the comfort and care of the patient and avoid the necessity of removing the vest if emergency cardiovascular resuscitation is needed. In the treatment of lesions of the lower part of the cervical spine (caudad to the level of the fourth cervical vertebra), the use of a halo vest that extends caudad to the level of the twelfth ribs does provide additional stability.

Posterior strut fusions to enhance immediate postoperative cervical stability.

UNLABELLED: In an attempt to enhance the immediate stability of posterior interspinous fusion constructs, the authors conducted the following project. Twenty-four adult mongrel dogs underwent a posterior C4-C5 fusion using iliac crest autogenous graft and internal fixation using either ulna struts (12) or metallic struts (12) fixed into position by sublaminar wires. Half of the animals were killed at either 1 week or 3 months postoperatively, and their C4-C5 motion segments were excised and studied radiologically, mechanically, and histologically. Both fusions created immediate and 3-month stability equivalent or superior to normal C4-C5 canine spinal segments. However, three dogs were rendered completely and two dogs incompletely quadriplegic by the surgery. CLINICAL RELEVANCE: Because of the relatively high rate of neurologic injury associated with these procedures in normal dogs, the authors hesitate to endorse their use in all but complete quadriplegic patients.