Gait change after local anesthetic of chronically arthritic knee.

Gait alterations of chronic knee arthritis before and after injection of local anesthesia was measured in the orthopedist's office area. A portable gait analyzer was used to evaluate gait characteristics before and after injection of local anesthesia in the chronically arthritic knee. Gait was analyzed during a 400-meter walk. Overall velocity and cadence increased 3.3% (p = 0.016) and 2.8% (p = 0.005). In-stance phase single and double support time (SLS and DLS) reduced 1.3% (p = 0.003) and 3.8% (p = 0.028). The ratio of SLS/DLS increased confirming a relatively increased duration in SLS as a percentage of the overall gait cycle. In swing phase the pulling power (initial swing), swing power (terminal swing) and ground impact increased 10.3% (p < 0.001), 6.8% (p = 0.003), and 4.2% (p = 0.003). Patients demonstrated fatigability at the end of walking measured as diminished velocity. Fatigability decreased after injection of the arthritic knee. The study demonstrates the specific gait phase changes afforded by injection of local anesthesia into the chronically arthritic knee. This study may serve as a benchmark for the measure of possible improvements afforded by different therapy for the patient suffering from chronic knee arthritis.

Radiological changes in second- and third-generation Zweymüller stems.

The Alloclassic and Endoplus femoral stems have the same grit-blasted surface and are hot forged from the same titanium alloy. Only the external form of the implants differs slightly. It was our aim to examine the differences in radiographic bone response between the Alloclassic (second generation) and the Endoplus (third generation) femoral stems. We compared 79 prostheses in 70 matched patients studied over a minimum of two years. Radiolucent lines, adaptive bone remodelling, subsidence, heterotopic bone formation and lysis were recorded in the Gruen zones. Radiolucencies were mainly found in zones 1 and 7 but to a greater extent in the Endoplus than in the Alloclassic group (p < 0.001 in zone 1, p < 0.05 in zone 7). We found lucent lines in three or more Gruen zones in seven patients all of whom were in the Endoplus group (p < 0.05). Zones 2 and 6 had a significantly higher rate of lucencies in the Endoplus group (p < 0.001). We encountered a combination of proximal lucent lines in zones 1 and 7 with distal hypertrophy of the cortical bone in zones 2, 3, 5 and 6 in eight patients, all from the Endoplus group (p < 0.05). In other patients bone atrophy (stress shielding) in zones 2 and 6 was seen more frequently in the Endoplus than in the Alloclassic group (p < 0.001). In neither group was there radiological evidence of osteolysis. Heterotopic bone formation and subsidence occurred with similar frequency in both groups. Our study shows that a small change in the form of the femoral implant can result in statistically significant radiological changes in bone remodelling. Whether this will result in clinical compromise is unknown. However, it seems likely that the Endoplus femoral stem will perform differently from the Alloclassic.

Morphometric examination of straight, tapered titanium stems: a retrieval study.

Cementless straight, tapered rectangular cross section titanium stems have been used by the senior author since 1979. Thirty-four stems retrieved postmortem, after between 10 days and 15.2 years in situ, were studied morphometrically and histologically. Nineteen stems were first generation (1979-1986), with an incomplete sagittal taper and a mean surface roughness of 1 microm (Ra 1.23 +/- 0.3 microm); 15 stems were second generation after 1986, with a full biplane taper and a mean surface roughness of 4 microm (Ra 4.14 +/- 0.36 microm). Implant surface bony coverage was determined morphometrically in 10 segments of the stems, and expressed as a bone implant contact index. Histologically, there were no differences between implants with different levels of roughness. Morphometrically, the first-generation stems showed significant differences in coverage (distal > proximal); second-generation stems had a more uniform pattern. Stems retrieved early after arthroplasty had a mean bone implant contact index of 10%. The mean bone implant contact index showed attainment of maximum coverage by 5 years after arthroplasty, without additional apposition or loss thereafter. Patients younger than 65 years at arthroplasty had similar bone implant contact indices to patients 65 years or older; coverage in the six patients 80 years of age at retrieval did not differ from the rates in the other patients. Morphometry was able to provide objective evidence of design change effects. No differences in coverage were found in terms of times in situ, patient age at arthroplasty and at retrieval, and degree of stem surface roughness.

Dermal hypoesthesia after total knee arthroplasty.

Dermal hypoesthesia is a well-recognized sequelae of total knee arthroplasty (TKA). However, it is poorly documented. Thirty-five knees were evaluated for hypoesthesia among 26 patients after TKA to determine the incidence, area affected, and change over time in situ. All knees sustained an area of hypoesthesia, showing diminution over time. All were affected lateral to the medial parapatellar incision. A 71% decline of the area affected was seen over the first 2 years after surgery. All patients had some residual hypoesthesia with a mean of 33 cm2 at 2 years.

Variation in hospital charges for total joint arthroplasty: an investigation of physician efficiency.

Total joint arthroplasty is a common procedure for which consistent, clinically satisfactory outcomes are expected. Data from 796 total joint procedures performed by 20 surgeons at one center were evaluated to identify sources of variability in costs (as measured by hospital charges) where clinical outcome is expected to remain constant. Stepwise multivariate regression characterized the contribution of six variables to hospital charges listed in order of explanatory power: postoperative length of stay, surgical time, patient preoperative morbidity, units of blood transfused, perioperative complications, and procedure type (hip or knee) accounted for 46% of variability in hospital charges (multiple R2). In a subsequent analysis, after statistical adjustment for preoperative comorbid diagnoses, the sampling distribution of mean values for surgical time, total units of blood transfused, and total hospital charges were summarized and compared among surgeons. Despite adjustment for comorbid diagnoses, substantial variation and significant differences remained between surgeons in markers of resource utilization and "surgical efficiency." These findings suggest there is substantial variability in hospital charges not attributable to patient characteristics or category of procedure--a distinct and economically significant portion of this variability is practitioner specific.

Degenerative changes in normal femoral heads in the elderly.

Unipolar hemiarthroplasty and bipolar hemiarthroplasty are frequently chosen for treating subcapital hip fracture; however, clinical outcome varies substantially. Although total hip arthroplasty is indicated for subcapital hip fracture in patients with degenerative hip disease, there is a lack of data on the incidence and extent of degenerative change in patients with subcapital hip fracture without obvious degenerative hip disease. This investigation evaluated articular cartilage in 25 consecutive femoral heads removed from elderly patients who sustained acute femoral neck fracture. All patients' femoral heads demonstrated grade 2 or 3 chondromalacia with an average involvement of 54% of the whole femoral head surface area. Review of the literature describes the cost-to-benefit ratio associated with painful hip arthroplasty. This study demonstrated a high incidence of femoral head degenerative change, which may account for the variable clinical results and proliferation of the term unsolved fracture. In the patient with a subcapital hip fracture, total hip arthroplasty may prove to be a better alternative.

Assessment of press-fit hip femoral components retrieved at autopsy.

Eleven femurs with press-fit titanium hip components were retrieved at autopsy for clinical, radiographic, and histologic evaluation. Back-scattered electron microscopy (BEM), bone densitometry, and appositional bone index studies also were performed. The average patient age was 87 years; the average time in situ was 22 months (range: 2 to 60). All patients were functioning well and pain free. Radiographs and bone mineral density studies (BMD) showed mild proximal stress shielding in five cases. No cases of osteolysis or pedestal formation were observed. Histologic sections revealed an average of 26% bone-prosthesis contact. Bone surrounding the prosthesis appeared viable, and osteoclastic activity in the interfacial bone was minimal; the presence of macrophages and inflammatory cells was rare. The appositional bone index averaged 40%. Bone-prosthesis contact was seen consistently at the corners of the component in the multiple regions, mostly were prosthesis-endosteal cortical contact was made. BEM demonstrated intimate contact of bone with the rough titanium surface. Bone mineral density was lower in the lesser trochanter and medial proximal regions of the implanted femur than in the contralateral femur. Evidence of bone on-growth fixation in 11 femoral components suggests that cementless, stable bone fixation may be achievable in senior individuals and that "complete fit and fill," porous-coated, cementless prostheses may not be required for prosthesis stability.

Human postmortem retrieval of total hip arthroplasty.

Postmortem retrieval of well-functioning prostheses from total hip arthroplasty is essential in determining the quality and success of the implant, implant fixation, and operative technique. This report describes the retrieval procedure, including details on informed consent, retrieval procedure, and types and benefits of specimen analysis. Bone densitometry, roentgenography, and microscopy studies permit a level of assessment of operative and prosthetic performance not obtainable from clinical and in vivo roentgenographic evaluation alone. Findings from these techniques yielding data on stress shielding, bone mineral density, extent of bone-prosthesis apposition and osseointegration, and histologic activity are ultimately of considerable clinical significance. The implementation of retrieval programs, along with establishing early family and patient cooperation and proper planning practices, will continue to contribute invaluably to advances in orthopaedic science.

Microscopic studies of human press fit titanium hip prostheses.

Seven cementless, press fit, rectangular cross section, titanium alloy femoral prostheses were implanted for the treatment of displaced subcapital hip fractures in elderly patients and retrieved postmortem for microscopic evaluation. The mean patient age was 88 years (range, 66-103 years), and prostheses were in situ an average of 29 months (range, 6-45 months). Microscopic examination of the specimens revealed regions of bone to prosthesis contact without interposed connective tissue, and all were considered stably osseointegrated. The mean microscopic bone to prosthesis contact for five cross sections was 28%. Implantation of this prosthesis achieved satisfactory primary stability in endosteal cortical bone in these elderly patients. Secondary stabilization was apparent, as evidenced by new, viable bone formation and remodeling in apposition to the prosthesis.

Cross-section radiographic analysis of 10 retrieved titanium alloy press-fit femoral endoprostheses.

Ten cementless, press-fit, rectangular cross-section, titanium alloy prosthetic hips were implanted in the treatment of 9 displaced subcapital hip fractures and 1 case involving degenerative joint disease in 9 elderly patients (1 patient with bilateral implants) with varying Dorr bone types. Femur-implant constructs were retrieved postmortem for radiographic evaluation. Specimens remained in situ an average of 27 months (range, 6 weeks to 60 months). The mean patient age at retrieval was 87 years (range, 66-103 years). After retrieval, 2-mm-thick transverse sections were made at 5 levels along each implant. Radiographs were then made of each transverse section. Extensive bone-to-prosthesis apposition, remodeling, and the consistent mineralization of bony structures extending from the endosteal cortex to the implant were noted. The appositional bone index was measured for each patient, and the mean index (across all levels) between patients ranged from 15% to 74% overall mean, 48%. Radiographic and clinical findings demonstrated the ability of the titanium alloy material and the design of the press-fit implant to achieve satisfactory primary and secondary stability in elderly patients.

100-year-old patient with pressfit prosthesis: a postmortem retrieval study.

A 100-year-old woman underwent a pressfit hemiarthroplasty for treatment of a hip fracture. She was ambulant, pain free, and died 45 months after surgery. Her femurs were retrieved for analysis. Clinical, radiographic, histologic, and densitometric evaluations suggested stable bone fixation. Histologically, intimate bone contact with the prosthesis ranged from 14% to 25% over six transverse sections throughout the length of the component. Bone densitometry was generally equal to the nonimplanted femur, except at the medial cortex. Few osteoclasts or inflammatory cells were noted. Most new bone was noted at the corners of the implant. These results suggest that cementless pressfit fixation may be achievable in elderly patients and that osteointegration and prosthetic stability is possible without a complete "fit and fill."

Flexion-type Salter II fracture of the proximal tibia. Proposed mechanism of injury and two case studies.

An uncommon fracture of the proximal tibial epiphysis is described in two cases. A flexion-type Salter II fracture of the proximal tibia resulting from a partially closed physis can be reduced easily and appears to have no long-lasting effects. Radiographic review of the adolescent knees showed that physeal closure of the proximal tibial epiphysis proceeds from posterior to anterior, thereby making this particular fracture more likely during this phase of development.

Gait electromyographic evaluation of the long-toe flexors in children with spastic cerebral palsy.

In a prospective study of the phasic activity of the long-toe flexors of patients with spastic cerebral palsy, the electrical activity of the long-toe flexors in 37 children with varus or valgus hindfoot deformity was measured by wire electrode dynamic electromyography. Although gross abnormalities in the phasic timing of the flexor hallucis longus and flexor digitorum longus were observed, these muscles could not be implicated in the etiology of hindfoot deformity. In planning gait analysis protocols for children with cerebral palsy and hindfoot deformity, electromyography of the long-toe flexors is not necessary unless toe curling is clinically evident.

Single stage lengthening by intercalary bone graft in patients with congenital hand deformities.

The experience with single-stage lengthening by intercalary bone graft in four patients with congenital hand deformities is presented. In all seven lengthenings the gap was bridged by a toe phalanx bone graft. The elongation of the ray ranged from 5-14 mm. Examination of patients followed from one to five years after the treatment showed a good appearance of the lengthened ray. One bone graft assimilation resulted in a pseudoarthrosis and another had osteopenia that resolved spontaneously. All others healed uneventfully. The quality of the skin sensitivity, vascular status and tendon balance is preserved after the lengthening.

"Idiopathic" scoliosis associated with congenital upper-limb deficiency.

Sixty patients with congenital upper-limb deficiency were evaluated for scoliosis in 1972. Twenty-one patients had scoliosis of 5 degrees or more and 15 had scoliosis of 10 degrees or more. Fifteen of these patients had long-term follow-up periods. Thirteen patients had idiopathic scoliosis. Idiopathic scoliosis associated with congenital upper-limb deficiency could be divided into three groups, and the progression of scoliosis was predictable within each group. All but one of these patients had a relatively benign course and did not require treatment. Double curves with rotation progressed throughout the growth period. Double curves with Grade 0 rotation tended not to be progressive. Single curves did not have rotation deformity and resolved spontaneously or remained stable. Magnitude of limb deficiency did not correlate with the curve magnitude, progression, or pattern. Muscle imbalance did not appear implicated as a cause for the scoliosis in these patients. Young age at discovery of the curve did not correlate with progression of the curve.

The stabilizing effect of soft-tissue constraints in artificial Galeazzi fractures.

Shortening of the radius is observed in Galeazzi (Piedmont) fractures and results from muscle pull after distal radioulnar joint disruption. A cadaver study was designed to examine the normal laxity at the distal radioulnar joint and contributions of the fibrocartilaginous complex (triangular ligament) and the interosseous membrane in prevention of proximal displacement of the distal radius fragment. It was found that up to 5 mm of radial shortening occurred after osteotomy alone. Shortening of over 10 mm did not occur unless both the interosseous ligament and the triangular ligament were sectioned. Some Galeazzi-type fractures may occur in the absence of distal radioulnar joint disruption, and others may result in disruption of the interosseous membrane of the forearm in addition to disruption of the triangular ligament at the wrist. Diaphyseal fractures of the distal radius may occur in several stages of severity. Attempts to produce a Galeazzi lesion by axial loading and pronation of the forearm above the dorsiflexed wrist caused a variety of injuries but did not result in an isolated fracture of the distal radius or disruption of the distal radioulnar joint.

Functional demands on the stance limb in walking.

In normal human locomotion, the lower extremities must maintain the erect posture while at the same time permitting forward progression of the body. Walking involves a complex interplay of gravity, momentum changes, and muscle action. A quantitative analysis of the effects of gravity and momentum changes on the stance limb in normal gait has been performed. These effects, represented by the ground reaction force, impose challenges to the muscles of the lower extremity. The nature of the torques about the hip, knee, and ankle joints has been investigated and correlated with the timing of muscle action throughout the gait cycle. Mechanical events in the earliest part of stance phase have been more clearly described than in previous work. Analysis of the effects of gravity and momentum changes improves our understanding of the mechanics of normal walking, and can aid in the diagnosis and treatment of disabled patients.

Surgical treatment of plantar fasciitis.

Ten patients were operated on for plantar fasciitis (12 heels) by stripping the plantar fascia and superficial plantar muscles from the calcaneus. All patients were refractory to conservative treatment for an average of 12.4 months prior to operation and were followed up for a minimum of 24 months after operation. Complete symptomatic relief was obtained in all patients despite the presence of massive obesity in six. Hypoesthesia of the heel, which was present in five feet after operation, may have enhanced pain relief. Three patients who were receiving workmen's compensation returned to work within 16 weeks of surgery. One deep wound infection occurred and required surgical debridement before healing could occur. Surgical treatment is efficacious in selected cases of plantar fasciitis that are refractory to conservative measures.