Kenneth A. Johnson

Tibialis posterior tendon dysfunction.

Dysfunction of the tibialis posterior tendon evolves through a series of stages. The pain symptoms, clinical signs, and roentgenographic changes for each of these stages are characteristic. This staging system permits clarification and individualization of dysfunction, expected pathologic changes, and surgical treatment. The importance of the tibialis posterior tendon in normal hindfoot function and its treatment when injured are now being properly appreciated.

Tibialis posterior tendon rupture

Rupture of the tibialis posterior (TP) tendon occurs most commonly in adult women. It evolves as an insidious, painful, and progressive flatfoot deformity. Watching for such deformities as too many toes and including the single heel rise test in the examination will facilitate an accurate diagnosis. The treatment rationale should consider the site and extent of tendon disruption, as well as the presence of secondary deformity. Early treatment will help to prevent long-term functional impairment.

Bone Loss and Reduced Osteoblast Function in Primary Biliary Cirrhosis

The association of bone loss with primary biliary cirrhosis is poorly understood. In 15 premenopausal female patients, only 2 of whom had fractures, mean bone mineral density was reduced at the lumbar spine but not at the midradius or distal radius. Bone loss was not statistically related to the duration or severity of liver disease. Urinary hydroxyproline excretion, an index for bone resorption, was not different from that of 15 age-matched normal women, but the serum concentration of bone Gla-protein (osteocalcin), a specific marker for bone turnover, was decreased (p less than 0.001). Bone histomorphometric examination in 13 patients showed no osteomalacia but a reduced bone formation rate despite normal values for fractional osteoblast-osteoid interface. The substantial early loss of trabecular bone is mediated by a severe reduction in osteoblast function, which may be caused by retained toxic substances associated with cholestasis.

Tibiotalocalcaneal Arthrodesis with an Intramedullary Device

An intramedullary fixation device was devised by the senior author (K.A.J.) to use in conjunction with a previously described method for tibiotalocalcaneal arthrodesis. Satisfactory results were obtained in approximately 87% of the initial 30 patients; union was radiographically or clinically evident in all but two patients. Many of these patients had been offered or were considering below the knee amputation; only two ultimately chose this reconstructive option at a follow-up that ranged from 4 to 27 months.

Radiographic Measurements of the Normal Adult Foot

Various radiographic measurements of the normal adult foot have been reported in both early and recent literature; however, a complete description of radiographic quantitative data has yet to be reported. The purpose of this study is to describe the range of the normal foot using standard radiographic techniques that can be applied to the clinical setting. This should provide the data necessary for the accurate interpretation of foot radiographs. This study demonstrates the wide variation in bony relationships of the normal adult foot. When certain recognized criteria of radiographic measurements were evaluated, some were found to be defined as too narrow or inaccurate. Most importantly, because of this wide range, surgical procedures to produce radiographic homogeneity are not indicated. Treatment should be directed specifically toward areas of pain and not radiographic appearance.

Subjective Results of Hallux Rigidus Following Treatment with Cheilectomy

The records of 58 patients who had hallux rigidus and were treated with cheilectomy between 1977 and 1984 showed the following results: 53.4% completely satisfactory, 19% mostly satisfactory, 27.6% unsatisfactory. No deterioration of results with time was apparent. When the results were analyzed in relation to the degenerative changes that were evident in the preoperative roentgenograms, the failure rate was increased from 15% with Grade I changes to 37.5% with Grade III changes. Cheilectomy is the procedure of choice in patients with hallux rigidus and Grade I changes.

Chevron osteotomy for hallux valgus.

The chevron osteotomy for realignment of the first metatarsal head in metatarsus primus varus deformity has been utilized at the Mayo Clinic since 1976 on 26 feet (18 patients). Follow-up evaluation disclosed excellent relief of pain, good cosmetic correction, and overall patient satisfaction. Radiographic evaluation demonstrated reduction in the angle between the phalanx and the metatarsal bone of the great toe as well as narrowing of the forefoot with a decreased angle between the first and the second metatarsal bones. The stability of the osteotomy, the technical ease, and the absence of secondary difficulties such as transfer metatarsalgia make this procedure preferable when osteotomy of the distal portion of the first metatarsal bone is used for correction of moderate deformity.

The Assessment of Dynamic Foot-to-Ground Contact Forces and Plantar Pressure Distribution: A Review of the Evolution of Current Techniques and Clinical Applications

The objective documentation of foot function before and after therapeutic intervention will be greatly enhanced by the utilization of devices capable of measuring dynamic foot pressure distribution. Efforts to develop this technology date back to the late 19th century, but only with recent advances in computers has it been possible to produce quantitatively accurate high resolution foot pressure distribution with high sampling rates and easily interpreted graphic displays. Over the years, a variety of methods have been employed to study foot pressure. Many of these techniques have already improved our understanding of the foot and its function, and have had an impact on the way we practice. Effective clinical utilization of these new investigative tools depends on an understanding of their scientific basis, capabilities and limitations.

Tibiotalocalcaneal arthrodesis for arthritis and deformity of the hind part of the foot.

We devised a method for tibiotalocalcaneal arthrodesis to treat deformities or degenerative arthritis, or both, that involve the tibiotalar and talocalcaneal joints. Satisfactory results were obtained in approximately 75 per cent of twenty-one patients; osseous union was radiographically evident in all but three patients. Secondary degenerative changes in the adjacent joints were not evident radiographically during a period of follow-up that ranged from 2.5 to seven years.

A Review of Ruptures of the Achilles Tendon

Rupture of the Achilles tendon is a relatively infrequent injury that is often missed by the initial treating physician. The diagnosis can be established on the basis of the physical examination with weakness of plantarflexion, a palpable gap in the tendon, and a positive squeeze test. Special diagnostic studies are rarely necessary. In the majority of cases, the etiologic basis for the rupture appears to be a combination of intratendon degeneration and mechanical stress. Conservative treatment of an acute rupture by immobilization with a cast provides satisfactory results. For the younger, more athletic patient, surgical repair should be considered.