Development of Open Backend Structures for Health Care Professionals to Improve Participation in App Developments: Pilot Usability Study of a Medical App.

BACKGROUND: Efficient digitization in medicine still is in its infancy but undeniably has great potential for current and future challenges in health care. Thus far, the rollout of medical apps has not resulted in widespread use of smartphones in the German health care sector-the reasons for this have not been clarified so far. Nevertheless, the lack of user involvement in the development process and content creation might contribute to low acceptance of these products. OBJECTIVE: This study aims to outline an approach to involve medical expertise without any coding knowledge for developing medical app content and functions. METHODS: An end user-operable backend was built. Its usability was evaluated using a usability evaluation test protocol. The results of the usability tests were evaluated by the app development team, and the usability test was repeated for optimizing backend usability. In total, 40 criteria to measure the ease of app usage were defined a priori. The usability test comprised 20 tasks that had to be fulfilled. Usability tasks were analyzed for completion, dropout, and test duration. Due to the COVID-19 pandemic, digital videoconferencing platforms (Zoom and QuickTime Player) were used to complete usability questionnaires. Finally, several backend-based apps for several specialties (infectiology, plastic and reconstructive surgery, and orthopedics) were developed by health care professionals as prototypes. RESULTS: Initial usability testing was conducted with 5 participants (4 men and 1 woman; mean age 39.2, SD 5.97 years). All of them could complete the assigned backend tasks with only a few workflow interruptions and some minor errors. After usability optimization, the workflow completion time decreased from 5.03 minutes to 3.50 minutes, indicating a time saving. The basic backend structure was clear to all test users and the handling was intuitive to learn. Some minor errors in the backend occurred during the test rounds. The apps developed using the aforementioned approach are in clinical use as a proof of concept. CONCLUSIONS: Backends offering operability for medical professionals might have great potential for app development in the mobile health sector. Sophisticated and time-saving usability are pivotal for the acceptance of medical software, as illustrated by the backend-based apps presented herein, which are in clinical use as a proof of concept. Basic interventions are essential and sufficient for adequate usability optimization. Practicable, well-structured software usability evaluation is possible based on the usability evaluation test protocol.

[Subtalare Screw Arthroereisis for the Treatment of Symptomatic, Flexible Pes Planovalgus]. / Die subtalare Schraubenarthrorise zur Behandlung des symptomatischen, flexiblen Pes planovalgus ­ Ergebnisse und eine aktuelle Literaturübersicht.

BACKGROUND: The purpose of this study was to determine the functional outcomes and radiographic results of the talus-stop screw method as minimally invasive subtalar arthroereisis in pediatric and juvenile flexible flatfoot. MATERIAL AND METHODS: We retrospectively evaluated 73 feet from 41 children using the talus stop-screw method, for the period between 2002 and 2011. The age at time of surgery ranged between nine and 14 years. The radiological assessment included measuring the calcaneal pitch, talar declination, talo-first metatarsal angle (Meary) and calcaneal-first metatarsal angle (Costa-Bartani) in the lateral view. To evaluate talo-navicular alignment in the anteroposterior view, the talo-first metatarsalbase angles were measured. To describe the amount of planovalgus deformity in lateral and anteroposterior view, we determined a tarsometatarsal-index by adding the talo-first metatarsal and talo-first metatarsal base angles. RESULTS: 95% of patients were satisfied or very satisfied with postoperative results for morphology, pain and activity level. 95% of patients exhibited no limitations in daily life or sports activity due to foot pain, fatigue or repetitive distorsion. 96% of patients would undergo the surgery again, if necessary. Full weight bearing could be achieved after a mean time of 8.1 (range, 2 - 21) days. All measured postoperative angles improved significantly, except talar inclination. CONCLUSIONS: The talus-stop screw method as a minimally invasive subtalar arthroereisis is a safe and effective treatment for the flexible pes planovalgus deformity in children and adolescents. It preserves canalis tarsi and its proprioceptive structures. The major complication rate is low and, with a vertically inserted cancellous screw, this is an economic procedure. The TMT-index incorporating both planes in pes planovalgus feet appears to be a more precise method to determine this multiplanar deformity and to evaluate treatment options and results.

Treatment of isolated peroneus longus tears and a review of the literature.

BACKGROUND: Isolated peroneus longus tendon tears are rare and represent a frequently overlooked source of lateral ankle pain and dysfunction. Only few cases of isolated peroneus longus tendon tears have been reported and a common treatment algorithm does not exist. The purpose of this study was to give an overview of the literature and to present our experience of 6 consecutive cases that have been treated successfully by operation and immobilizing cast. METHODS: A comprehensive chart review was performed to compile each patient's age, sex, onset of symptoms, time between first symptoms and diagnosis, surgical findings, surgical treatment, length of follow-up, and outcome. The average patient age was 48 years (range 20-63 years). RESULTS: Acute tears occurred in 4 cases, and 2 patients reported about a chronic onset of symptoms. The cause for acute tears was an acute inversion ankle sprain in all cases. Diagnosis was made after an average of 11 months (range 0.75-24 months). There were 2 complete tears, and other 4 were incomplete. An os peroneum was present in 2 cases. In 5 of 6 cases, the results after surgical treatment were excellent or good after a mean follow-up of 28.6 months (range 12-78 months). CONCLUSION: This study indicates that lateral ankle pain may be due to isolated acute or chronic peroneus longus tendon tears. Thorough clinical and radiological diagnosis is necessary to detect this uncommon injury in time. Patients with acute onset of symptoms and short time between symptoms and diagnosis tend to fare better than the chronic tears and delayed diagnosis. Surgical intervention yields successful and predictable results.

Surgical treatment of AVN of the fibular (lateral) sesamoid.

Despite the fact that the hallucal sesamoids play a crucial role in forefoot mechanics, disorders resulting from pathology of these structures are often overlooked or misdiagnosed. Avascular necrosis (AVN) of the hallucal sesamoids is a rare condition that must be differentiated from other pathologies, such as fractures, pseudarthrosis or osteomyelitis. We report on two patients with AVN of the fibular (lateral) hallucal sesamoid (Morbus Renander). In both patients the necrotic part of the fibular sesamoid was excised surgically after failed conservative therapy. The followup was 29 and 26 months. The clinical and radiological results showed a complete relief of pain in both patients without any complications or forefoot deformities. Recent literature and own experiences support non-operative initial management including anti-inflammatory medications, shoe modification and temporary limited weight bearing. If symptoms persist, surgical treatment with excision of the necrotic part of the sesamoid may be an alternative. Consideration by the surgeon should be given to protecting the neurovascular bundle and reattaching intrinsic tendons and ligaments if necessary. Satisfying results can be achieved by surgical removal.

[Cheilectomy and Kessel-Bonney procedure for treatment of initial hallux rigidus]. / Die Cheilektomie und Operation nach Kessel-Bonney zur Behandlung des initialen Hallux rigidus.

OBJECTIVE: Joint-preserving procedure for initial osteoarthritis of the first metatarsophalangeal joint for improvement of restricted joint motion and achievement of a harmonic gait. INDICATIONS: Hallux rigidus stage I and II according to Regnauld's classification. CONTRAINDICATIONS: Hallux rigidus Regnauld stage III. General medical contraindications to surgical interventions and anesthesiological procedures. SURGICAL TECHNIQUE: Operation in regional anesthesia (foot block). Tourniquet. Longitudinal skin incision over the dorsal aspect of the first metatarsophalangeal joint. Incision of the joint capsule with protection of the extensor hallucis longus tendon and the dorsal neurovascular bundle. Cheilectomy: removal of osteophytes at the metatarsal head and the base of the proximal phalanx. Resection of the dorsal third of the metatarsal head with an oscillating saw in plantar flexion of the proximal phalanx. Kessel-Bonney procedure: dissection of the proximal phalanx. Incomplete dorsal osteotomy with an oscillating saw at the metaphysis of the proximal phalanx and removal of a dorsal wedge with a base of 2-3 mm. Osteosynthesis with mini-plate or transosseous suture. POSTOPERATIVE MANAGEMENT: Postoperative elevation of the operated foot. Analgesia with nonsteroidal anti-inflammatory drugs. Postoperative shoe for 3-4 weeks. Immediate weight bearing. Mobilization of the metatarsophalangeal joint with an elastic bandage. Taping in extension and elastic forefoot dressing for 3 weeks postoperatively. Clinical and radiologic controls after 6 and 12 weeks. RESULTS: 53 operations on 45 patients were performed. 39 patients (86%; 28 female, eleven male, mean age 43.6 years) were followed up. After a period of 26 months (range: 10-51 months), 32 of 39 patients (82%) were satisfied or very satisfied. The median preoperative range of motion was 12.3 degrees for dorsal extension and 17.1 degrees for plantar flexion. Function had increased to a dorsiflexion of 34.2 degrees and a plantar flexion of 32.8 degrees. All patients returned to a normal walking ability after a mean period of 3.7 weeks. Due to delayed wound healing, one revision was necessary. According to Kitaoka's Forefoot Score, the mean preoperative value of 44.3 (standard deviation [SD]: +/- 16) increased postoperatively to a mean value of 78.9 (SD: +/- 12).