Neurosensory testing of the medial calcaneal and medial plantar nerves in patients with plantar heel pain

Eighty-two patients with a chief complaint of plantar heel pain were evaluated for sensory abnormalities within the cutaneous distribution of both the medial calcaneal nerve and the medial plantar nerve, using quantitative neurosensory testing with a pressure-specified sensory device. The results showed that 22.68% of the patients displayed isolated abnormal sensory function within the distribution of the medial calcaneal nerve, whereas 49.48% of the patients displayed abnormal function within the distribution of both the medial calcaneal and the medial plantar nerves. Thus, 72.17% of the patients displayed abnormal sensory function within the distribution of the medial calcaneal nerve. Statistical analysis of the results, using the Pearson chi-square statistic and odds ratio, indicated that a significant percentage of patients with plantar heel pain, even early in the clinical course of plantar heel pain, display abnormal sensibility within the branches of the posterior tibial nerve, and specifically, within the distribution of the medial calcaneal nerve (P <.0008) and the medial plantar nerve (P <.0001).     

Innervation of three weight-bearing areas of the foot: an anatomic study and clinical implications.

The aim of this cadaver study is to improve our knowledge on the anatomy of the sensory fibres of the three weight-bearing areas of the plantar region. Previous studies mainly focused on the innervation of the heel but the innervation of the other two weight-bearing areas over the most medial and lateral metatarses have been neglected and are not well known. The study was carried out on 10 feet of five male cadavers. The tibial nerve was dissected down to the fat pads over the heel and the first and fifth metatarsal heads under the microscope. The distances of the branching point of the tibial nerve and origins of the medial and inferior calcaneal nerves to a line drawn from the centre of the medial malleolus to the centre of the calcaneous were all measured. The tibial nerve was divided into two branches called the lateral and medial plantar nerves 23.45 mm proximal to the predefined axis. The medial plantar nerve passed underneath the abductor hallucis muscle and gave two sensory branches to the fat pad over the first metatarsal head. The lateral plantar nerve coursed beneath the abductor hallucis and flexor digitorum brevis muscles and supplied innervation of the fat pad over the fifth metatarsal head. The sensory innervation of the heel was provided by medial calcaneal and inferior calcaneal nerves. The medial calcaneal nerve originated from the tibial nerve 41.89 mm proximal to the axis. It divided into two or three branches innervating the fat pad over the heel. The inferior calcaneal nerve originated from the lateral plantar nerve (70%) or the medial calcaneal nerve (30%) 10.66 mm proximal to the axis. This study describes the sensory fibres to the heel and the previously neglected weight-bearing areas over the first and fifth metatarses. Reconstruction of defects in these areas is very difficult so every attempt should be made to protect the sensory fibres during any surgical procedure.     

Neuromas of the calcaneal nerves.

A neuroma of a calcaneal nerve has never been reported. A series of 15 patients with heel pain due to a neuroma of a calcaneal nerve are reviewed. These patients previously had either a plantar fasciotomy (n = 4), calcaneal spur removal (n = 2), ankle fusion (n = 2), or tarsal tunnel decompression (n = 7). Neuromas occurred on calcaneal branches that arose from either the posterior tibial nerve (n = 1), lateral plantar nerve (n = 1), the medial plantar nerve (n = 9), or more than one of these nerves (n = 4). Operative approach was through an extended tarsal tunnel incision to permit identification of all calcaneal nerves. The neuroma was resected and implanted into the flexor hallucis longus muscle. Excellent relief of pain occurred in 60%, and good relief in 33%. One patient (17%) had no improvement and required resection of the lateral plantar nerve. Awareness that the heel may be innervated by multiple calcaneal branches suggests that surgery for heel pain of neural origin employ a surgical approach that permits identification of all possible calcaneal branches.     

Percutaneous pin placement in the medial calcaneus: is anywhere safe?

OBJECTIVE: To redefine the medial calcaneal anatomic safe zone for pin placement with respect to reproducible palpable landmarks. DESIGN: Anatomic study. SETTING: Medical school anatomy laboratory. INTERVENTIONS: Thirty-three fresh-frozen adult cadaveric feet were used. Three palpable anatomic landmarks were identified on each ankle and labeled as Point A (posteroinferior medial calcaneus), Point B (inferior medial malleolus), and Point C (navicular tuberosity). The medial neurovascular bundle was carefully dissected, and the medial calcaneal nerve, the most posterior branch of the lateral plantar nerve, the lateral plantar nerve, the medial plantar nerve, and the posterior tibial artery were identified. These structures were recorded at the point at which they transected a line from Point A to B and from Point A to C. Based on the findings of the first thirty-three feet, two pins were placed percutaneously into the medial calcaneus of ten additional feet. Pin 1 was placed one half the distance from Point A to B. Pin 2 was placed one third the distance from Point A to C. The neurovascular structures were then dissected and identified in relation to the pin position. RESULTS: The medial calcaneal, most posterior branch of the lateral plantar, and lateral plantar nerves are at significant risk for abutting the pins or being directly injured at the margins of these relative safe zones. CONCLUSION: The medial calcaneus provides a small window for safe percutaneous pin placement. Posterior to the halfway point from Point A to B and posterior to the one-third mark from Point A to C remain the relatively safest regions; a more posterior placement in the safe zone is safest. Careful blunt dissection and the use of cannulas may help to avoid neurovascular injury.     

Plantar fascia release through a transverse plantar incision.

A transverse plantar incision for plantar fascial release was assessed for pain relief, numbness, and subsequent heel pad symptoms. Twenty-seven feet in 26 patients who underwent plantar fascia release were reviewed with a minimum follow-up of 2 years after surgery (average, 37.6 months). Comprehensive data were obtained on 25 feet (24 patients) (93% response rate). The plantar fascia origin was completely transected in all cases. This led to complete resolution of symptoms in 19 feet and residual minor symptoms in six feet. After 2 years, four patients had developed recurrent symptoms, two in the area of surgery and two on the dorsum of the foot, in association with a pes planus foot. Two patients had some continued persistence of heel pain after surgery, although significantly less pain than preoperatively.Thus, 76% of patients had complete relieve of there symptoms, 12% of patients had mild symptoms not affecting daily activities, and 12% of patients had moderate symptoms that limited some activities. No patient suffered heel pad symptoms or numbness after surgery. It is concluded that plantar fascia release through a transverse plantar incision is a successful procedure for long-term relief of symptoms which avoids unnecessary heel pad numbness and scar morbidity. The benefits of a transverse incision include greater intraoperative vision, to ensure adequate release and spur excision, and an incision parallel to the medial calcaneal branches of the tibial nerve.     

An anatomical study of tarsal tunnel

In order to understand the pathogenesis and improve the treatment of tarsal tunnel syndrome, we investigated the tarsal region anatomically on 62 feet of 31 cadavers and five freshly amputated feet. The following results were thus obtained: 1. The bifurcation into the medial and lateral plantar nerves mostly occurred within the flexor retinaculum. 2. The medial calcaneal branch showed many anatomical variations. 3. The flexor retinaculum was not clearly demarcated at its superior and inferior borders, and it was not as thick as previously thought. 4. The neurovascular bundle was separated from other tendon sheaths, and enclosed in its own tunnel. 5. A fibrous septum found at the entrance of the abductor hallucis muscle, may represent an entrapment point of the medial plantar nerve. 6. The ganglion from the talocalcaneal joint tended to compress only the medial plantar nerve.     

Reconstruction of plantar heel defect using reinnervated, skin-grafted flexor digitorum brevis flap

Two cases with extensive plantar avulsion injuries had their heel defects resurfaced initially with full thickness skin grafts. Two months later, reinnervation presented in areas of grafted skin innervated by medial and lateral plantar nerves. No reinnervation was found in the plantar heel region originally innervated by the medial calcaneal nerve. Heel ulceration in the non-sensate, grafted skin occurred in the first case. Reinnervated, skin-grafted flexor digitorum brevis muscle flaps were then used for reconstructing the non-sensate plantar heels. There was no breakdown of skin during the follow-up period of 8 months and 6 months respectively. This method provides sensate and durable cover for extensive plantar heel defects.     

The inferior calcaneal spur—Anatomical and histological considerations

BackgroundThe inferior calcaneal spur has long been associated with inferior heel pain. Traditionally, many physicians have believed the spur to be associated with the plantar aponeurosis, though more recently others report the spur to lie within the intrinsic musculature of the plantar rear foot. While previous anatomical studies have generally involved cadaveric specimens, there is a relative paucity of research which has specifically analysed the spur of surgical samples from symptomatic heels.ObjectivesThis study was carried out to investigate the nature, affiliation and histopathology of the heel spur and the tissue in which the spur resides.MethodsHeel spur samples were taken from five healthy participants undergoing open heel surgery for recalcitrant inferior heel pain involving the presence of a heel spur.ResultsThe inferior calcaneal spur was found to lie consistently within the origin of the intrinsic musculature of the first layer of the plantar aspect of the foot. The plantar aponeurosis proper was observed to course inferior to the heel spur and had attachment to the spur along the spur's inferior margin. Microscopically, the entheses of the intrinsic musculature of the first layer and the plantar aponeurosis were amalgamated to form a single broad origin of the inferior medial calcaneal tubercle. The spurs lacked a cortical shell and endochondral ossification was a prominent feature. Overt fracture of the heel spur itself was a common finding.ConclusionsObservations largely suggest a weight-bearing compressive disturbance, with secondary traction of the respective enthesis–bone unit as the underlying cause of spur growth. In this series, spurs were noted to manifest by means of endochondral ossification.     

Observations on the fibrous retinacula of the heel pad

BACKGROUND: The original purpose of the study was to clarify whether or not there is continuity of the Achilles tendon and the plantar fascia. Those findings have been previously published. In the course of that study, observations of the anatomy of the retinacular tethers of the heel pad were made. These observations included the discovery of the medial calcaneal retinaculum. METHODS: Ten adult cadaver feet were dissected. A longitudinal midline incision was made along the Achilles tendon and on the plantar surface of the foot. The heel pad was incised and the skin and heel pad were reflected side-to-side to reveal the calcaneal tuberosity. In this way the retinacular tethers of the heel pad could be seen. RESULTS: Two types of retinacular fibers were observed. Abundant small retinacula were seen coming off the plantar fascia and calcaneal tuberosity. Less abundant larger retinacula originated from the calcaneus only. Both types anchored the heel pad by branching into the fibrous stroma of the heel pad. In nine of 10 feet, a much larger retinacular structure was the principle tether of the heel pad to the medial process of the calcaneal tuberosity. We named this the medial calcaneal retinaculum. CONCLUSIONS: The heel pad is anchored by retinacula that vary in number, location, and size. The most consistent and significant tether of the heel pad appears to be the medial calcaneal retinaculum. CLINICAL RELEVANCE: Dislocation of the fat pad of the heel is a relatively rare but potentially devastating injury. An understanding of the anatomical anchoring of the heel pad and its mechanical function can lead to a surgical procedure to restore stability to the heel pad.     

跗管综合征的应用解剖学研究

目的:为跗管综合征的诊治提供形态学基础。方法:对61例成人下肢标本的跗管进行观测。结果:(1)跗管可分为前室、后浅室和后深室,胫神经、胫动静脉位于浅后室内;(2)跗管内容物有3％的变异率;(3)足内外侧神经分叉部59％位于踝跟轴线上方,26％位于下方,9％平轴线;(4)跟神经2支及2支以上者占51.3％。57.8％的跟神经来源于足外侧神经,35.4％来自胫神经,6.8％来自足内侧神经。结论:任何导致后浅室内高压的因素均可引起跗管综合征,手术以松解后浅室为主,各神经支的解剖变异在诊治时应加注意。     

采用KobeGurd系统行跖腱膜部分切断术治疗顽固性跟痛症的疗效

背景：跟痛症是足踝外科的常见病,目前临床主要通过保守方法治疗。但对于保守治疗无效或反复发作的病例,手术治疗也许是一种不错的选择。目的：观察足跟内侧小切口KobeGurd系统跖腱膜部分切断术治疗顽固性跟痛症后患者症状改善情况,探讨利用该方法治疗顽固性跟痛症的可能性。方法：2008年8月至2011年3月采用小切口KobyGard系统进行足跟内侧跖腱膜部分切断术治疗顽固性跟痛症患者68例,其中资料完整的56例（84足）,男24例（32足）、女32例（52足）,体重80 kg以上者46例。年龄28~72岁,平均47.6岁。病史均1年以上,最长者3.6年,平均1.8年。手术前后及末次随访时观察包括疼痛强度（VAS评分系统）、行走距离、站立时间、跟骨筋膜压痛及踝关节、距下关节的活动度等的临床疼痛指数变化,并进行后足疗效评定。结果：本组患者随访时间11~36个月,平均17个月。所有患者跟骨处疼痛完全消失,行走步态恢复正常。疼痛指数：术前平均为8.8,术后4周、8周、4个月、8个月分别为4.89、2.98、1.46和0。根据美国足踝外科协会Maryland后足百分评分法对本组患者进行评定,优66足（78.6%）,良16足（19.1%）,可2足（2.3%）。未出现跟骨骨折、足弓塌陷等并发症。结论：运用小切口KobeGurd系统跖腱膜部分切断术治疗顽固性跟痛症疗效满意,可作为临床治疗顽固性足跟痛的一种选择。     

跟骨内外侧经皮置针安全区解剖学研究

目的 划定国人跟骨内、外侧外固定针进针位置解剖学相对安全区.方法 解剖14具正常成年人足踝部标本.于跟骨内侧取跟骨最内下后点为A点,内踝最下点为B点,足舟骨结节为C点.解剖出跟骨内侧神经、足底外侧神经最后分支、足底外侧神经、足底内侧神经、胫后动脉、足底外侧动脉和足底内侧动脉.根据各结构行经AB、AC线的位置,确定跟骨内侧的相对安全区;于跟骨外侧取跟骨最外下后点为D点,外踝最下点为E点,解剖出跟骨外侧神经、腓肠神经、小隐静脉主干,同理确定跟骨外侧的相对安全区.结果 跟骨内侧神经、足底外侧神经最后分支、足底外侧神经、足底内侧神经、胫后动脉分别行经AB线后下22%、50%、56%、64%及58%处,跟骨内侧神经、足底外侧神经最后分支、足底外侧神经、足底内侧神经、足底外侧动脉、足底内侧动脉分别行经AC线后下14%、39%、49%、63%、41%及57%处.跟骨外侧神经、腓肠神经、小隐静脉分别行经DE线后下 19%、65%及61%处.结论 在跟骨内侧,AB线后1/2、AC线后1/3所在圆形区域为经皮置针相对安全区.在跟骨外侧,经DE线中点垂线后方的跟骨为经皮穿针相对安全区.     

关节镜筋膜深层入路治疗跖筋膜炎

目的观察关节镜筋膜深层入路治疗跖筋膜炎的临床疗效。方法对17例经至少1个月正规非手术治疗效果不理想的单足跖筋膜炎患者在关节镜下筋膜深层入路行清理跟骨骨赘、切断跖筋膜内侧1/3~1/2术。术后1年采用AOFAS踝-后足评分标准评估足踝功能。结果17例患者均获得随访,时间12~19个月。术后患足完全负重时间7~14 d。AOFAS踝-后足评分术前57.0分±7.4分,术后1年91.7分±5.2分,差异有统计学意义(P<0.001)。1例术后残留足跟部疼痛,经非手术治疗疼痛缓解。结论关节镜筋膜深层入路治疗跖筋膜炎创伤小、视野清楚、术后恢复快、效果确切。     

The thickness of heel fat-pad in patients with plantar fasciitis

ObjectiveThe aim of this study was to investigate the thickness of heel fat pad (THP) and to detect the relationship between the plantar fasciitis (PF) and age, occupation, BMI, longitudinal arch, the thickness of heel fat-pad in the patients with PF.MethodsA total of 50 patients (29 women and 21 men; mean age: 46.5 years (range: 22–70)) that were diagnosed with PF were included to this study. Patients' affected side were compared with the healthy opposite side with the angle of medial arch (AMA) and first metatarsophalangeal angle (FMTPA) on the foot radiograms, and THP and thickness of first metatarsal fat pad (TFMFP) using ultrasonography (USG) of both feet.ResultsThe mean AMAs of feet with pain and without pain were 122.56° and 120.60°, respectively. The mean FMTPAs of feet with pain and without pain were 14.72° and 14.40°, respectively. The mean THPs of feet with pain at the point of the medial calcaneal tubercle and the mean TFMFPs of the feet with pain at the point of the first metatarsal head were 19.45 mm and 6.75 mm, respectively. The mean THPs of feet without pain at the point of the medial calcaneal tubercle and the mean TFMFPs of the feet without pain at the point of the first metatarsal head were 19.94 mm and 6.75 mm, respectively. It was observed that the mean AMA in the heels with pain was significantly higher than that of the heel without pain (p < 0.05) and the mean THP in the heels with pain was significantly thinner than that of the heel without pain (p < 0.05).ConclusionThe results indicate that USG is an accurate and reliable imaging technique for the measurement of THP in the diagnosis of plantar fasciitis and the heel pad was thinner in the painful heels of patients with plantar fasciitis.Level of evidenceLevel III, Diagnostic Study.     

Outcome of neurolysis for failed tarsal tunnel surgery

Revision tarsal tunnel surgery was performed on 44 patients (two bilaterally). The surgical procedure included a neurolysis of the tibial nerve in the tarsal tunnel, the medial plantar, lateral plantar, and calcaneal nerves in their respective tunnels, excision of the intertunnel septum, and neuroma resection as indicated. A painful tarsal tunnel scar or painful heel was treated, respectively, by resection of the distal saphenous nerve or a calcaneal nerve branch. Postoperative, immediate ambulation was permitted. Outcomes were assessed with a numerical grading scale that included neurosensory measurements. Outcomes were also assessed by patient satisfaction and their own estimate of residual pain and/or numbness. Mean follow-up time was 2.2 years. Outcomes in terms of patient satisfaction were 54% excellent, 24% good, 13% fair, and 9% poor results. The mean preoperative numerical score was 6.0 and the mean postoperative score was 2.7. There was a significant improvement seen, based on the median difference between scores (P<0.001). Prognostic indicators of poor results in our patient group were coexisting lumbosacral disc disease and/or neuropathy. An approach related to resecting painful cutaneous nerves and neurolysis of all tibial nerve branches at the ankle offers hope for relief of pain and recovery of sensation for the majority of patients with failed previous tarsal tunnel surgery.     

Endoscopic treatment of calcaneal spur syndrome: A comprehensive technique

We describe a comprehensive approach to the endoscopic treatment of calcaneal spur syndrome developed by the Arthroscopic Group of the Orthopedic Service of Hospital Hermanos Ameijeiras in Havana, Cuba. The surgical technique involves treatment of the heel spur and plantar fasciitis commonly found in calcaneal spur syndrome, but it also addresses adjacent calcaneal periostitis and allows decompression of the nerve to the abductor digiti quinti. Medial endoscopy and lateral instrumentation are used in a sequential approach with exposure and debridement of the posterior roof of the calcaneal arch, followed by removal of the calcaneal spur, lateral to medial release of the medial 75% of the plantar fascia, and if necessary, debridement of the calcaneal tuberosity periosteum. This technique was used in a prospective case series from June 1997 to May 1998 to treat a select group of 38 feet in 30 patients who reported unacceptable levels of pain despite 5 months of conservative treatment, which included an aggressive 8-week physical therapy program prescribed by the treating physician. Good to excellent results were obtained at 3 months postoperatively in all patients with regard to pain relief and return to normal activity, although 5 patients required a short course of physical therapy to resolve symptoms brought on by sports, trauma, or impact loading before 1-year follow-up, at which time all patients reported good to excellent results. Complications included 3 superficial wound infections cured by oral antibiotics and 2 transient lateral paresthesias that resolved with rest and nonsteroidal inflammatory medications. The described technique may provide a useful method for treating refractory heel spur syndrome and warrants further study.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 5 (May-June), 2001: pp 517–522     

Biomechanical evaluation of two clinical tests for plantar heel pain: the dorsiflexion-eversion test for tarsal tunnel syndrome and the windlass test for plantar fasciitis

BACKGROUND: Plantar heel pain may result from several conditions such as tarsal tunnel syndrome (TTS) and plantar fasciitis. The dorsiflexion-eversion test is used to diagnose TTS, whereas the windlass test is used for plantar fasciitis. Given the similarity between both tests, the purpose of this study was to evaluate whether these tests are able to selectively load the structures which they aim to examine. METHODS: Both tests were evaluated in six cadavers by measuring strain in the plantar fascia, tibial nerve, lateral plantar nerve (LPN), and medial plantar nerve (MPN) using miniature displacement transducers. Longitudinal excursion of the nerves was measured with a digital caliper. RESULTS: With the dorsiflexion-eversion test, dorsiflexion and eversion of the ankle in combination with extension of the metatarsophalangeal (MTP) joints significantly increased strain in the tibial nerve (+1.1%), LPN (+2.2%), and MPN (+3.3%) but also in the plantar fascia (+1.2%) (all: p=0.016). Both components (dorsiflexion-eversion and MTP extension) resulted in significant increases. With the windlass test, extension of all MTP joints significantly increased strain in the plantar fascia (+0.4%, p=0.016), but also in the tibial nerve (+0.4%, p=0.016), LPN (+0.8%, p=0.032) and MPN (+2.0%, p=0.016). Excursion of the nerves was always in the distal direction but only reached significance for the tibial nerve (6.9 mm, p=0.016) and LPN (2.2 mm, p=0.032) during the dorsiflexion-eversion test. CONCLUSIONS: Both tests mechanically challenge various structures that have been associated with plantar heel pain. This questions the usefulness of the tests in the differential diagnosis of plantar heel pain.     

Plantar Fascia Release Through a Single Lateral Incision in the Operative Management of a Cavovarus Foot: A Cadaver Model Analysis of the Operative Technique

Plantar fascia release and calcaneal slide osteotomy are often components of the surgical management for cavovarus deformities of the foot. In this setting, plantar fascia release has traditionally been performed through an incision over the medial calcaneal tuberosity, and the calcaneal osteotomy through a lateral incision. Two separate incisions can potentially increase the operative time and morbidity. The purpose of the present study was threefold: to describe the operative technique, use cadaveric dissection to analyze whether a full release of the plantar fascia was possible through the lateral incision, and examine the proximity of the medial neurovascular structures to both the plantar fascia release and calcaneal slide osteotomy when performed together. In our cadaveric dissections, we found that full release of the plantar fascia is possible through the lateral incision with no obvious damage to the medial neurovascular structures. We also found that the calcaneal branch of the tibial nerve reliably crossed the osteotomy in all specimens. We have concluded that both the plantar fascia release and the calcaneal osteotomy can be safely performed through a lateral incision, if care is taken when completing the calcaneal osteotomy to ensure that the medial neurovascular structures remain uninjured.     

A touch pressure sensory assessment of the surgical treatment of the tarsal tunnel syndrome

Background

Decompressive tarsal tunnel surgery may improve dysfunctional plantar foot sensation in, patients with tarsal tunnel syndrome and peripheral neuropathy. However, quantitative sensory, assessment is lacking.

Method

Quantitative sensory threshold evaluation of 42 feet in 37 consecutive (29 non-diabetic and 8 diabetic) patients was done before and after surgical decompression for tarsal tunnel syndrome. Insensitivity was documented quantitatively (grams force) before and after surgery using a graded series of twenty Semmes–Weinstein monofilaments applied to the anatomic nerve regions of the plantar aspect of the foot.

Results

Sensory evaluation at an average of 12 months after surgery showed significant improvement, of mean sensory threshold, compared with preoperative values, for medial calcaneal, medial plantar, and lateral plantar nerves.

Conclusion

Quantitative sensory assessment with a graded series of twenty Semmes–Weinstein, monofilaments showed significant sensory improvement in the medial calcaneal, medial plantar, and, lateral plantar nerves after posterior tibial nerve decompression.