Lesser metatarsal osteotomies. A biomechanical approach to metatarsalgia.

As with most other orthopedic conditions, a firm understanding of the normal and pathologic biomechanics of the lesser metatarsals is essential when contemplating treatment of metatarsalgia. Despite its prevalence, metatarsalgia remains a technically demanding surgical challenge. Some of the difficulty with treatment of this problem arises because of some of the controversies discussed previously. Many lesser metatarsal osteotomies have been described, and their success depends on many factors. Alleviating the correct amount of pressure underneath the metatarsal head without adversely affecting the biomechanics of the region demands an exacting osteotomy that is stable and readily heals. Much of the research done to date has not proved which procedure can achieve these goals reproducibly for patients. It is hoped that future investigations will guide treatment choices and allow patients to obtain relief from this difficult problem with greater success.

Diagnosing and treating plantar fasciitis: a conservative approach to plantar heel pain.

Plantar fasciitis is the most common cause of pain at the weight-bearing surface of the heel, and may coexist with other sources of heel pain. This has led to a confusing array of treatment strategies, including surgery. We offer a simple, effective diagnostic and treatment algorithm that emphasizes nonsurgical treatment options for this often frustrating condition.

Diagnosing and treating hallux valgus: a conservative approach for a common problem.

For most patients with hallux valgus, the problem is caused by wearing shoes that are too tight, and conservative measures can help. We review how primary care physicians can evaluate and treat this problem, and when to refer to an orthopaedic surgeon.

Talonavicular arthrodesis for the painful adult acquired flatfoot.

Twenty-seven consecutive patients with posterior tibial tendon insufficiency were treated with talonavicular arthrodesis as the primary stabilizing procedure. Twenty-six patients were followed a minimum of 12 and an average of 27 months. Twenty-four patients had either no pain or pain only after heavy usage. Eleven patients were completely satisfied with postoperative foot function, 13 were satisfied, with minor reservations, and 2 were satisfied, with major reservations. Results were rated as excellent in 10 patients, good in 14 patients, and fair in 2 patients. Successful arthrodesis was achieved in all patients, although one patient required two additional bone grafts. Progressive arthrosis in adjacent joints was noted in five patients, four of whom had arthrosis preoperatively. No deterioration of foot position was seen in any patient with follow-up as long as 5 years. An isolated talonavicular arthrodesis seems to offer patients with this disorder both reliable pain improvement and lasting stability.

Chronic plantar heel pain: treatment with a short leg walking cast.

The efficacy of a short leg walking cast in the treatment of chronic plantar heel pain was assessed for 32 patients with 37 involved extremities treated over a 2-year period. All patients had failed numerous other treatment modalities and had been symptomatic for an average of 1 year. Long-term follow-up for 24 patients with 28 involved extremities revealed complete resolution of pain for 7 extremities (25%), improvement for 17 (61%), and no improvement for 4 (14%). Ten (42%) patients were completely satisfied with cast treatment, 3 (12%) were satisfied with reservations, and 11 (46%) were dissatisfied. Casting appears to be a reasonable option for patients with recalcitrant heel pain and should be offered before surgical intervention.

Effects of hydroxyapatite tricalcium phosphate coating and intracancellous placement on bone ingrowth in titanium fibermetal implants.

The purpose of this study was to compare the host-bone response to hydroxyapatite/tricalcium phosphate (HA/TCP)-coated and noncoated titanium fibermetal implants placed in a load-sharing cancellous bone environment of the distal femurs of rabbits. The influence of implantation site was also investigated by comparing these intracancellous implants with intramedullary implants evaluated in a previous study. Three parameters were measured: percentage implant perimeter surface length in contact with new bone, percentage internal fibermetal surface length in contact with ingrown bone, and percentage of available pore space filled with bone. The HA/TCP coating significantly accelerated and increased bone ongrowth, new bone formation on the perimeter and internal surface of the implants. This effect was evident as early as 2 weeks after implantation. In contrast, there was no difference between HA/TCP-coated and noncoated implants in the bone ingrowth parameter, percentage of available pore space filled with bone, or pull-out strength. Scanning electron microscopy in the backscatter mode demonstrated that new bone formed directly onto the HA/TCP-coated fibers and did not usually form directly on noncoated fibers. Analysis of fluorochrome labeling revealed that bone formation in weeks 1 through 4 was primarily woven and thereafter lamellar. Compared with intramedullary placement, intracancellous placement significantly accelerated the apposition of bone to the perimeter and internal surface of HA/TCP-coated implants and both accelerated and increased bone ingrowth as a percentage of available pore volume. These data show that the host response to titanium fibermetal implants is influenced both by HA/TCP coating and by the implantation site.

Triple arthrodesis for diabetic peritalar neuroarthropathy.

From 1963 to 1990, the senior authors (R.E.M. and K.G.H.) performed eight triple arthrodeses in seven patients with diabetes mellitus with sensory loss in the lower extremities. By clinical and roentgenographic examination, all patients were diagnosed with peritalar neuroarthropathy before surgery. All patients underwent a two-incision triple arthrodesis with internal fixation. Patient follow-up averaged 44 months and included repeat physical examinations and radiographs. All patients went on to clinical union and were satisfied with the procedure. One patient had prolonged wound drainage that resolved with antibiotic therapy; another had a residual rocker-bottom deformity and plantar ulceration that resolved after modification of custom shoe wear. We believe comprehensive management of diabetic peritalar neuroarthropathy can include surgical arthrodesis of the involved joints. The disease process and surgical indications are discussed.

The influence of a hydroxyapatite and tricalcium-phosphate coating on bone growth into titanium fiber-metal implants.

A study was done in rabbits to determine the effect of a hydroxyapatite and tricalcium-phosphate coating on bone growth into titanium fiber-metal implants. Titanium fiber rods with a solid titanium core were implanted bilaterally into the distal aspect of the femora of fifty-five New Zealand White rabbits. One rod was uncoated and the other rod was surface-coated with hydroxyapatite and tricalcium phosphate by the plasma-spray technique. Thirty-five rabbits were labeled sequentially with fluorochromes; killed at one, two, three, four, six, twelve, or twenty-four weeks after the operation; and studied histologically and histomorphometrically. The implants in the remaining twenty rabbits were subjected to pull-out testing to determine the shear strength at the implant-bone interface at three, six, twelve, and twenty-four weeks after the operation. Histomorphometry revealed significant effects of the hydroxyapatite and tricalcium-phosphate coating. When whole-group means (which included all time-points) were compared, it was found that 44 per cent of the perimeter of the hydroxyapatite and tricalcium-phosphate-coated implants was covered with bone compared with 12 per cent of the perimeter of the uncoated implants. The percentage of the internal surface of the implant that was covered with bone was also significantly higher in the hydroxyapatite and tricalcium-phosphate-coated implants: 27 per cent of the internal surface of the coated implants was covered compared with 8 per cent in the uncoated implants. The amount of bone in the pores of the implants was also higher in the hydroxyapatite and tricalcium-phosphate-coated implants: 12 per cent of the available pore space in the hydroxyapatite and tricalcium-phosphate-coated implants was filled with bone compared with 4 per cent in the uncoated implants. Scanning electron microscopy of the implants, done in backscatter mode, demonstrated apposition of new bone directly on the hydroxyapatite and tricalcium-phosphate coating, with variable degrees (amounts) of hydroxyapatite and tricalcium-phosphate resorption and new-bone replacement over time. Bone was never directly apposed to uncoated titanium fiber-metal. The pull-out strength of the hydroxyapatite and tricalcium-phosphate-coated implants was consistently greater than that of the uncoated implants, at all time-periods.