Summary Statement

Treatment of non-union is a highly demanding field with respect to bone healing. BMP 7 is a useful, wide-ranged tool in treating non-union of the foot and benign bone tumors. It represents a low-risk procedure with a high level of reliability.

Background: The chevron osteotomy is a widely accepted method for the correction of mild to moderate hallux valgus deformity that reveals good to excellent results in terms of radiographic correction of hallux valgus deformity as well as functional outcome scores. However, recent pedobarographic studies have shown that there is decreased load of the big toe region and the first metatarsal head region respectively at a short and intermediate-term follow-up Sufficient load of these structures is essential in order to provide physiological gait patterns. The purpose of the present study was to determine if a modification in the postoperative regimen improves the functional outcome of chevron osteotomy for correction of hallux valgus deformity.

Methods: 29 patients with an mean age of 58 years who suffered on mild to moderate Hallux valgus deformity without radiographic signs of osteoarthritis of the first MTP joint who underwent chevron osteotomy were included in this prospective study. Postoperatively patients were placed in a forefoot relief shoe for 4 weeks. After this period they received a multimodal rehabilitation program including kryotherapy, lymphatic drainage, mobilisation, manual therapy, strnthening exercises and gait training. The patients received a mean of 4.2 treatment sessions and the sessions took place one time a week for 3 to 6 weeks. Preoperatively and one year after surgery plantar pressure distribution parameters including maximum force, contact area and force-time integral were evaluated. Additionly the AOFAS score, ROM of the first MTP and plain radiographs were assessed. The results were compared using Student’s t-test and level of significane was set at p< 0.05.

Results: In the big toe region maximum force increased from 72.2 N presurgically to 106.8 N at one year after surgery, contact area increased from 7.6 cm2 preoperatively to 8.9 cm2 one year postsurgically and force-time integral increased from 20.8 N*sec to 30.5 N*sec. All changes were statistically significant.(p< 0.05) For the first metatarsal head region maximum force increased from 122.5 N presurgically to 144.7 N one year after surgery and force-time integral increased from 42.3 N*sec preoperatively to 52.6 N*sec one year postoperatively. However, those changes were not statistically significant. (p=0.068; p=0.055)The mean AOFAS score increased from 61 points preoperatively to 94 points at follow-up (p< 0.001). The average hallux valgus angle decreased from 31° to 9° and the average first intermetatarsal angle decreased from 14° to 6° respectively.(p< 0.001)

Conclusions: The results of the present study indicate that postoperative physical therapy and gait training help to improve weight-bearing of the big toe and first ray respectively. Therefore, there is a restoration of physiological gait patterns in patients who recieve this postoperative regimen.

Introduction: Arthrodesis has been recommended for the treatment of end-stage osteoarthritis of the ankle joint, especially as the results of prosthetic ankle replacement are not comparable with those achieved with total hip or knee replacement. In vitro studies revealed that ankle arthrodesis restricts kinematics more than total ankle replacement in terms of range of motion as well as movment transfer. However, little is known about in vivo gait patterns in patients with arthrodesis of the ankle joint.

Aim of this retropective study was to determine plantar pressure distribution in patients who underwent ankle arthrodesis with a standardized screw fixation technique in a single surgeon population.

Methods: 21 patients (7 male/14 female) who underwent isolated unilateral ankle arthrodesis with 3 crossed 7,3 mm AO screws (Synthes Gmbh, Austria) in a standardized technique by a single surgeon between October 2000 and January 2008 have been included in this study. At a mean follow-up of 25 months (range 12 – 75) pedobarograhy (Novel GmbH., Munich), clinical evaluation using the AOFAS hindfoot score and weight-bearing x-rays of the foot were performed.

Results: Pedobarographic assessment revealed no statistically significant difference between the operated foot and the contralateral foot eighter in terms of peak pressure, maximum force, contact area and contact time or the gait line parameters velocity of center of pressure, lateral-medial force indices or lateral-medial area indices.

The average AOFAS score was 80,5 (range 46 – 92) and mean tibioplantar angle determined on the lateral standing radiograph was 91° (82° – 100°). Non-union didn’t occur in any patient.

Discussion: The results of the present study indicate that ankle arthrodesis restores plantar pressure distribution patterns to those of healthy feet. Therefore, the functional outcome of ankle arthrodesis seems to be good as long as the fusion is in fixed in an appropriate position.

Introduction: The modified Lapidus-arthrodesis with standard AO screw-fixation is well known for the treatment of severe metatarsus primus varus deformity respectively a hypermobile or an arthrotic first tarso-metatarsal joint. High rates of non-union and malunion (range 3 to 12%) due to improper or poor fixation despite the postoperative course of nonweightbearing were reported in literature. The immediate postoperative weightbearing protocol varies from 2 to 6 weeks of cast immobilization. To our knowledge, this prospective investigation comprises the largest cohort of patients undergoing the Lapidus-arthrodesis, fixed with the Lapidus-Orthner locking plate.

Methods: 130 feet with an average patient’s age of 52 years (range 23 – 83 years), underwent the Lapidus fusion with the locking Orthner-plate. Indications were severe hallux valgus deformities respectively moderate hallux valgus deformities with a hypermobile first TMT 1- joint or an arthrotic first tarsometatarsal joint. The surgical technique was standardized, and the operations were performed by the inventor of the plate. All patients had a failed trial of nonoperative management (shoe-wear modification).

The 130 feet were divided into 2 groups. Group I was without TMT 1 – compression screw (n= 60) and group II with an additional compression-screw (n=70). Average age of group I was 54-years. The average age of group II was 50-years. The American-Orthopaedic-Foot and Ankle Society (AOFAS) Forefoot-Score, Visual-analog-pain-scale and foot radiographs were assessed preoperatively and after a mean of 23 months for group I and 39 months for group II. All 130 feet were treated immediately postoperative with a postoperative Darco orthowedge ® shoe.

Results: The average AOFAS score improved significantly from preoperative to follow up time-point in both groups. AOFAS pain-subscore significantly improved in both groups. The intermetatarsal-angle (IMA) of all 130 feet decreased significantly from 14° to 6° after surgery. At time of follow-up 9 % of non-unions were seen in group I whereas 0% were seen in group II with proximal compression screw, the difference is significant (p=0,024). The mean immobilisation with the Darco-Ortho® wedge shoe was 7,2 weeks (range 6 to 14 weeks) in group I and 6,3 weeks (range 5 to 12 weeks) in group II.

Conclusion: The prospective mid-term results from this study show that the locking Lapidus-Orthner plate is a very good and promising technique for the Lapidus-arthrodesis. The modified technique with compression screw has shown none non-union, despite of immediate weight-bearing in a post-op shoe after surgery. The procedure significantly reduced pain, the hallux valgus and intermetatarsal angle and increased the patient’s ambulatory capacity and patient satisfaction.