Computed tomographic assessment of old calcaneal fractures

Open Reduction and Internal Fixation of a Calcaneal Anterior Process Fracture Using a Locking Plate

Fractures involving the anterior process of the calcaneus (APC) are rare, underdiagnosed, and carry a significant increase in morbidity if not identified acutely. Identifying patients with intra-articular fracture extension is crucial as they may benefit from surgical fixation to reduce the risk of morbidity and post-traumatic osteoarthritis. There are no specific guidelines in the United Kingdom regarding the management of these fractures, and there is little evidence regarding optimal management, mainly limited to case reports and small sample observational trials. Previous reports of surgical intervention have described excision of fragments or fixation using single cancellous screws.

A 55-year-old man fell from a height of 2 metres, sustaining an APC fracture extending into the calcaneocuboid joint. This was identified on plain radiographs following a virtual fracture clinic referral from the emergency department and further investigated with computed tomography scanning.

He underwent open reduction and internal fixation with a locking T-plate and screws three weeks post-injury to restore congruence of his articular surface. Following a period of non-weight-bearing and progressive physiotherapy, he reported an excellent functional outcome six months post-operatively, measured by the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score of 90%.

In the absence of specific guidelines for these fractures, this case provides an example of good initial functional outcomes following surgical fixation using a locking plate and screws, the first such fixation of an APC fracture described in the literature. This case can also be seen as a useful reminder of the need for an index of clinical suspicion for these injuries, given that up to 40% may be missed in the emergency department. While now fairly widespread, not all hospitals will have a virtual fracture clinic system in place, meaning emergency department practitioners must be wary of these injuries before discharging patients with suspicious histories and examination findings with no follow-up. Examination techniques that may help differentiate APC fractures from ankle sprains are discussed to provide clinicians with evidence to support a suspicion of these injuries in the emergency department.

Incidence of tendon entrapment and dislocation with calcaneus and pilon fractures on CT examination

OBJECTIVE

To examine the association between tibial pilon and calcaneal fracture classification and tendon entrapment or dislocation.

MATERIALS AND METHODS

After institutional review board approval, we retrospectively reviewed consecutive CT scans with calcaneal or pilon fractures from 5 years at a level 1 trauma center. We categorized calcaneal fractures according to the Sanders classification, and pilon fractures according to the Ruedi and Allgower and the Arbeitsgemeinschaft für Osteosynthesefragen-Orthopaedic Trauma Association (AO-OTA) classifications. Ankle tendons were assessed for dislocation or entrapment. Fisher's exact test was used for statistical analysis with significance at p < 0.05.

RESULTS

A total of 312 fractures (91 pilon only, 193 calcaneal only, and 14 ankles with ipsilateral pilon and calcaneal fractures) were identified in 273 patients. Twenty-two pilon, 42 calcaneal, and nine combination fractures were associated with 99 occurrences of tendon entrapment or superior peroneal retinacular injury. Such findings were associated with multiple fractures (p = 0.002). Multifragmentary pilon fractures were associated with posterior tibial and flexor digitorum longus tendon entrapment (p < 0.0001 and p = 0.0003 for Ruedi/Allgower and AO-OTA, respectively), and multifragmentary Sanders type 3 or 4 calcaneal fractures were associated with superior peroneal retinacular injury (p = 0.0473) compared to simple fracture patterns. Thirty-nine percent of tendon entrapments or retinacular injuries were prospectively identified, 85 % by musculoskeletal radiologists (p < 0.0001).

CONCLUSIONS

Approximately 25 % of calcaneal and pilon fractures were retrospectively identified to contain posteromedial tendon entrapment or superior peroneal retinacular injury. Radiologists should meticulously search for such injuries, particularly when analyzing multifragmentary and multiple fractures.

Distraction arthrodesis of subtalar joint using a laterally placed hinged distractor

Many joint-depressive, neglected calcaneal fractures need distraction arthrodesis of the subtalar joint. Because the calcaneal tuberosity is usually malunited in the varus position, more distraction is required on the medial side to place the tuberosity in the everted position before insertion of a bone graft. Traditionally, a distractor is placed on the medial side to achieve this task. However, the medially placed distractor hinders with the positioning of the extremity and exposure of the main operative site, which is commonly on the lateral side. We introduce a technique to avoid this burden by placing a hinged distractor device on the lateral aspect of the foot while maintaining the correction of the varus deformity.

Prognostic value of four classifications of calcaneal fractures

BACKGROUND

The purpose of this study was to assist surgeons treating calcaneal fractures in choosing the most predictive fracture classification and clinical outcome tool.

MATERIALS AND METHODS

For 152 patients (189 calcaneal fractures; average followup, 9.9 years), all fractures were classified in accordance with the Essex-Lopresti, OTA, Regazzoni, and Sanders classifications and matched with the following scores: AOFAS score, CNHF, FOA, MFS, Rowe, MFA, SF-36, and VAS.

RESULTS

The Essex-Lopresti classification showed no statistically significant relation with any of the clinical scores (p > 0.05). The OTA classification related statistically significant with the MFS (p = 0.006), AOFAS score (p = 0.013), FOA (p = 0.019), Rowe (p = 0.0027), and MFA score (p = 0.03). The Regazzoni classification correlated with the AOFAS score (p = 0.003), MFS (p = 0.002), Rowe (p = 0.002), CNHF (p = 0.0001), FOA (p = 0.003), MFA score (p = 0.002), and VAS (p = 0.005). The Sanders classification corrrelated with the AOFAS score (p = 0.007), MFS (p = 0.001), Rowe (p = 0.001), CNHF (p = 0.024), FOA (p = 0.021), MFA score (p = 0.036), and VAS (p = 0.014).

CONCLUSION

Compared to radiological based classifications, the CT based classifications, especially the Regazzoni and Sanders classifications, exhibited higher prognostic value compared to ultimate outcome scores.

Clinical outcome scoring of intra-articular calcaneal fractures

Outcome reporting of intra-articular calcaneal fractures is inconsistent. This study aimed to identify the most cited outcome scores in the literature and to analyze their reliability and validity. A systematic literature search identified 34 different outcome scores. The most cited outcome score was the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score, followed by the Maryland Foot Score (MFS) and the Creighton-Nebraska score (CN). Reliability (internal consistency) and validity (content, construct, and criterion) were determined for the 3 outcome scoring systems. Internal consistency (Cronbach's alpha, reliability) was similar for the Maryland Foot Score (alpha=0.82) and American Orthopedic Foot and Ankle Society hindfoot score (alpha=0.78), but lower for the Creighton-Nebraska (alpha = 0.61). Floor and ceiling effects were good for all 3 scores. The individual items within these outcome scores showing best content validity were pain, return to work, subtalar range of motion, walking distance, ankle range of motion, and gait abnormalities or limping. Construct validity was good for all individual items except sagittal motion, stability at physical exam, and shoe size. The 3 outcome scores showed high correlation with patient satisfaction as measured with a visual analog scale (VAS, criterion validity) and indication for an arthrodesis. In conclusion, pending consensus, we would recommend choosing between the widely accepted, reliable and valid AOFAS hindfoot and the Maryland Foot Score as the scoring systems of choice.

LEVEL OF CLINICAL EVIDENCE

2.

[The clinical use of the ISO-C(3D) imaging system in calcaneus fracture surgery]

We compared in a prospective study including 82 patients treated with ORIF of an intraarticular calcaneus fracture the quality of fluoroscopy, intraoperatively Iso-C(3D) and postoperative CT-scans. Therefore the posterior facet of the calcaneus (PFOC) was divided into three sectors. Joint steps and fracture gaps were detected by two independent investigators and statistically analysed. Another focus was to evaluate if the findings due to intraoperatively Iso-C(3D) assessment performed by the surgeon were correct and subsequently influenced the surgical procedure. There were no statistically differences between the Iso-C(3D)- and CT findings concerning joint steps or fracture gaps in PFOC sectors I-III. With fluoroscopy an assessment of the PFOC sectors I and II was not possible. In six cases (7.3%), intraoperative reduction was redone after performing an Iso-C(3D) scan. In ten cases, 12 malpositioned screws were replaced (12.2%/14.6%). These results suggest that intraoperative 3D Iso-C(3D) imaging provides a high diagnostic reliability. By careful assessment of the images the surgeons receive information which could lead to a change of the operative strategy.

Intra-articular calcaneal fractures treated nonoperatively and followed sequentially for 2 decades

OBJECTIVE

To assess the sequential and long-term patient outcome after nonoperative treatment of a displaced intra-articular calcaneal fracture, and to determine if initial results remain stable or deteriorate in the second decade after the injury.

DESIGN

Retrospective case series with sequential follow-up at 2 time points a decade apart.

SETTING

University teaching hospital.

MAIN OUTCOME MEASURES

At the first follow-up in 1990, hind feet were assessed with a computerized tomographic (CT) scan, radiographs, and with a 100 point score, the Iowa calcaneal score (ICS). At the second follow-up in 2000, the ICS was repeated and the patients completed the visual analog scale and the SF-36 questionnaire.

RESULTS

In 1990, 15 of 24 hind feet had good or excellent results on the ICS. Sixteen of 19 patients returned to their preinjury level of employment. Subtalar arthrosis on the CT scan correlated with lower average scores [64 points vs. 82 points (P < 0.035)]. Ten years later in 2000, the average ICS had decreased from 74 points to 64 points (P < 0.03); however, in patients with no or minimal arthrosis detected on the 1990 CT scan, the scores remained stable with an average of 82 points, in 1990, and an average of 81 points in 2000 (P < 0.61).

SUMMARY

These results suggest that after nonoperative treatment of closed displaced intra-articular calcaneus fractures, clinical results correlate with the presence of subtalar arthrosis on CT scans [except for those with grade V (spontaneous fusion)]. Patients with arthrosis grades III and IV have increased pain and deterioration in function in the second decade after injury compared with those with minimal arthrosis (grades I or II) or those who spontaneously fused their subtalar joint. Patients without arthrosis have good outcomes that remained stable over greater than 2 decades of follow-up.

CT guided diagnostic foot injections

AIM

To describe a CT technique for guiding diagnostic and therapeutic injections in the hind- and mid-foot.

MATERIALS AND METHODS

Over a period of 50 months, 28 individuals were referred for diagnostic and therapeutic hind- and mid-foot injections before possible arthrodesis. A CT technique was developed that allowed entry into the various joints using a vertical approach. Numbers of joints injected were as follows: posterior subtalar, 21; talonavicular, 4; calcaneonavicular, calcaneocuboid, navicular-cuneiform and 5th metatarsocuboid joints, 1 each.

RESULTS

All injections but one were technically successful. Significant relief of symptoms was noted by 16 participants, whereas for 9 there was no improvement and for 3 a partial response was achieved.

CONCLUSION

CT is a simple and safe alternative to fluoroscopy for guiding diagnostic and therapeutic foot injections, and may be the technique of choice in cases of disordered anatomy.

Treatment of os calcis fractures by open reduction and internal fixation

Over a 3-year period, 47 displaced intra-articular fractures of the os calcis in 43 patients underwent open reduction and internal fixation. A significant feature of this series is that computed tomography was used to assess all fractures both before and after surgery. Seventy-seven percent demonstrated a consistent fracture pattern with four major bone fragments. Patients underwent clinical assessment 1 year after injury; thirty-six feet (76.6%) were rated satisfactory and 11 (23.4%) were rated unsatisfactory. An unsatisfactory clinical outcome was significantly correlated with failure to obtain or maintain a satisfactory reduction (P = .004) and also with workers' compensation or liability status (P = .013). The degree of initial comminution, bilateralism, calcaneocuboid joint involvement, patient age, joint depression versus tongue-type fracture pattern, and Bohler's angle at follow-up did not correlate with the final clinical result. Postoperative computed tomography in the coronal plane was found to be mandatory for assessment of joint congruity and restoration of an adequate fibulocalcaneal space.

Computed tomographic assessment of soft tissue abnormalities following calcaneal fractures

Computed tomographic (CT) examinations of 50 acute calcaneal fractures were compared with a further series of 77 fractures in which the date of injury preceded the CT by 6 months or more. 42 (84%) of the fractures in the acute group and 55 (71%) in the chronic group were classified as intra-articular and they form the basis of this study. The alteration in the position of the peroneal tendons in the two groups was similar, with a 5% or less difference in each category. In the acute group the peroneal tendons were normally located in 40.4% of the cases, entrapped by bone in 11.9%, subluxed in 33.3% and dislocated in 14.2%. Structural abnormalities of the peroneal tendons and surrounding soft tissues were identified in 52.4% of the acute group and in 61.1% of the chronic group. The incidence of partial rupture of the peroneal tendons in the chronic group was approximately one third that in the acute group, but the low incidence of complete tendon rupture remained unchanged. The inference from these observations is that, in the majority of cases, partial peroneal tendon rupture is reversible, whereas complete rupture is not. Seven fractures were common to both series and from this limited group the identification of haemorrhage around the peroneal tendons in the acute phase was shown not to be related to the subsequent development of chronic stenosing tenosynovitis. Various abnormalities of the medial tendons of the hindfoot were identified in 17% of the acute group and in 18% of the chronic group. Following calcaneal fracture, CT in both the immediate post-fracture period and in the late phase can be used to detect and classify the soft tissue changes. The limitations of comparing the two groups in this study are discussed.