Patellofemoral pain syndrome (PFPS): a systematic review of anatomy and potential risk factors

Patellofemoral Pain Syndrome (PFPS), a common cause of anterior knee pain, is successfully treated in over 2/3 of patients through rehabilitation protocols designed to reduce pain and return function to the individual. Applying preventive medicine strategies, the majority of cases of PFPS may be avoided if a pre-diagnosis can be made by clinician or certified athletic trainer testing the current researched potential risk factors during a Preparticipation Screening Evaluation (PPSE). We provide a detailed and comprehensive review of the soft tissue, arterial system, and innervation to the patellofemoral joint in order to supply the clinician with the knowledge required to assess the anatomy and make recommendations to patients identified as potentially at risk. The purpose of this article is to review knee anatomy and the literature regarding potential risk factors associated with patellofemoral pain syndrome and prehabilitation strategies. A comprehensive review of knee anatomy will present the relationships of arterial collateralization, innervations, and soft tissue alignment to the possible multifactoral mechanism involved in PFPS, while attempting to advocate future use of different treatments aimed at non-soft tissue causes of PFPS

Isolated Intermetatarsal Ligament Release as Primary Surgical Management for Morton’s Neuroma

Category: Midfoot/Forefoot Introduction/Purpose: While the precise pathoetiology of Morton’s neuroma remains unclear, nerve inflammation as a result of chronic entrapment from the overlying intermetatarsal ligament (IML) may play a role. Traditional surgical management involved common digital nerve transection with neuroma excision, but this procedure risks unpredictable formation of a stump neuroma and potential worsening of symptoms. Accordingly, the senior author has over the past six years espoused isolated IML release and common digital nerve decompression in lieu of nerve transection or neuroma excision as an alternative treatment strategy. We hypothesized that IML release offers effective pain relief and high patient satisfaction level as a surgical treatment for recalcitrant Morton’s neuroma without the risk of stump neuroma formation or symptom exacerbation. Methods: Medical records for all consecutive patients treated surgically with isolated single interspace IML release for symptomatic and recalcitrant Morton’s neuroma over a four year period at a large academic medical center were examined. Any adult patient with clinically diagnosed Morton’s neuroma who had failed at least three months of conservative treatment and who then underwent single-webspace IML decompression were included. Any patient who had less than three months postoperative follow up, had undergone revisional neuroma surgery, or had undergone additional procedures at the time of the IML release were excluded. Overall patient satisfaction as well as pre- and post-operative Visual Analog Pain Scale (VAS) assessments were recorded for all patients. Results: Eleven patients underwent isolated, single interspace IML decompression for Morton’s neuroma over this time frame. One of these patients had a neuroma localized to the second web space and 10 were localized to the third web space. Average follow-up was 10.8± 9 (3-32) months (Table 1). VAS pain scores averaged 6.4 ± 1.9 (4-9) preoperatively and decreased to an average of 1.5 ± 1.6 (0-5) at final follow up (P = 0.003). All patients reported significant pain improvement and an overall satisfaction with the procedure (would undergo it again). No patients returned to the operating room, there were no postoperative infection nor worsening of pain, and no other complications were reported. Conclusion: Isolated single interspace IML release of chronically symptomatic Morton’s neuroma shows promising short-term results regarding pain relief and overall patient satisfaction, with few complications and no demonstrated risk of recurrent neuroma formation, permanent numbness, or postoperative symptom exacerbation. The authors’ collective experience with this approach has been positive enough over the past six years to result in the entire abandonment of the practice of neuroma excision in this patient population

Patient Comprehension of Foot and Ankle Surgery

Category: Other Introduction/Purpose: Health literacy represents a set of individual abilities which allow patients to assimilate information that helps them comprehend their medical condition and any interventions available for remedy. The purpose of this investigation was to determine the percentage of patients who— after undergoing the process of informed consent and being provided a postoperative instruction document—were then able to reach an elementary understanding of the pathology and requisite care associated with open reduction internal fixation of an ankle or foot fracture, osteotomy, fusion, or arthroscopy, including perioperative complications. Methods: Any patient who elected to have a foot or ankle surgical procedure that involved fracture, fusion, osteotomy, or arthroscopic management was recruited to participate in the study. Patients who were not deemed fluent in English were excluded. All patients were told that they would be asked to complete a questionnaire about their surgery and post-operative instructions. Enrolled patients were informed about the care and potential postoperative complications associated with their particular procedure during the informed consent process at the preoperative visit. All answers to each question of the questionnaire they would later receive were verbally given to each patient during this visit, and they were also given a post- operative instruction sheet that contained written answers to all these questions as well. At their first post-operative visit and prior to seeing the physician, all patients were then asked to complete this multiple choice questionnaire. The questionnaire was subsequently reviewed by the clinician with each patient at the end of this postoperative visit. Results: Forty-one patients were enrolled prospectively. Ninety percent (n=37) reported that they had read the postoperative instructions, and 92.7% (n=38) reported that they preferred a written handout versus a verbal, video, or on-line instructional alternative.. The average percentage of correct answers was 72.3% (7.95 out of 11 correct SD 1.4, 95% CI, 7.52 to 8.38). Only 43.9% (n=18) knew the correct response to ‘When can I return to driving an automatic vehicle?’. Only 53.7% (n=22) of patients knew ‘What is an appropriate protocol for icing immediately after surgery’. Chi square analysis of correct response count revealed no significant difference between patients with a high school versus higher level of education (p=0.22), males versus females (p=0.98), or age 18 to 30 versus over 30 years (p=0.59). Conclusion: Although we made significant pre-operative oral and written efforts to help patients achieve an elementary level of health literacy regarding their forthcoming foot or ankle surgery, we found that many continued to lack a baseline level of acceptable comprehension regarding numerous pertinent components of perioperative care and outcome. Because the results are concerning, we plan to next implement and test an alternative video aide to assess whether alternative forms of communication will increase comprehension and retention of surgical foot and ankle patients

Opioid Consumption Rate After Foot and Ankle Surgery

Category: Opioid consumption rate and risk factors investigation after foot and ankle surgery Introduction/Purpose: The rapid increase in the consumption of prescription opioids has become one of the leading medical, economical, and sociological burdens in North America. In the United States, orthopedic surgery is the fourth leading specialty in the number of opioids prescribed, and the largest among surgical specialties. There is insufficient evidence to guide surgeons about appropriate opioid prescription amounts after orthopaedic foot and ankle (F&A) procedures. The aim of this study was to determine the opioid consumption rate after foot and ankle procedures, and to identify patient risk factors associated with higher use. Methods: A total of 535 patients who underwent a F&A surgery performed by one orthopedic surgeon from August 2016 to March 2018 were investigated. The study was approved by our IRB. Each patient received a preoperative discussion about postoperative pain and expectations alongside a standardized handout. At the two-week postoperative visit, the patient-reported amount of consumed opioids was recorded. Prescription details, the amount of opioids taken, refill requests, pain-issue related telephone calls, and additional MD/ED visits were also documented. Patient demographics and co-morbidities, use of regional anesthesia, postoperative inpatient hospitalization, surgery type and severity, and pre-operative opioid use were collected retrospectively. Total amounts of morphine equivalents were calculated and converted into oxycodone 5 mg pills for standardization. P-values of <0.05 were considered significant. Results: Two hundred forty-four patients with a mean age of 50 years (±16.3) and a BMI of 29 (±6.1) were included. Sixty-six (27%) patients underwent a soft tissue procedure alone and 178 (73%) underwent a bony procedure. 225 (92.2%) patients received regional block. Patients reported that they consumed only 51.2% of prescribed pills after a bony procedure and 42.4% after a soft tissue procedure, respectively, which resulted in a total of 4,496.2 left over pills that derived from this study amongst only 244 patients enrolled. There were 11 refill requests (4.5%), two (0.8%) additional MD/ED visits, and 19 (7.8%) telephone calls related to pain. BMI, procedure type, and number of opioids prescribed were positively correlated with the consumption rate (P =.002, P<.001, P<0.001, respectively). Conclusion: BMI, surgery type (bony vs. soft tissue), and a higher number of pills dispensed were correlated with higher use in the postoperative period. After an educative discussion on postoperative pain, patients took 42.4% of the prescribed opioid after soft tissue procedures and 51.2% after bony procedures, resulting in a significant number of unused pills now available to the community. Future guidelines are necessary to improve our postoperative pain management, but this study suggests that current amounts of dispensed pills after orthopaedic F&A procedures are approximately twice as high as necessary

The Accuracy of 3D Measurements in Weightbearing Computed Tomography to Diagnose Lisfranc Instability

Category: Midfoot/Forefoot; Other Introduction/Purpose: Up to one-third of Lisfranc injuries are missed on initial evaluation, resulting in significant morbidity. Prompt diagnosis of Lisfranc injuries is, therefore, critical in optimizing outcomes, and yet there remains a lack of consensus on diagnostic criteria to identify Lisfranc instability using anatomic measurements. Prior studies have underscored the utility of weight-bearing computed tomography (WBCT) in diagnosing Lisfranc instability, which allows for bilateral three-dimensional (3D) evaluation under physiologic load. The aim of this study was to quantify appropriate cutoff values using 3D anatomic measurements of Lisfranc instability under physiologic load and as compared to the uninjured extremity. Methods: A total of 234 adult patients with bilateral WBCT scans of the foot were included: 43 patients with Lisfranc instability & 191 patients without a history of midfoot injuries. Lisfranc instability was confirmed intraoperatively or by clinical evaluation by the surgeon. Patients with prior midfoot surgery, Charcot arthropathy, severe midfoot arthropathy, or significantly displaced fracture of the cuneiforms or 1st, 2nd, or 3rd metatarsal bases were excluded. Lisfranc joint measurements were conducted bilaterally, including C1-M2 diastasis, C1-M2 area and 3D WBCT volume. Patient demographics were collected. Descriptive statistics were calculated for quantitative variables. Percent difference as compared to the contralateral side was calculated for volume, area, and diastasis. Mann Whitney U tests were utilized to determine differences in measurements between patients in the Lisfranc cohort and patients in the uninjured cohort (p-value < 0.05). Diagnostic cutoffs for Lisfranc instability were determined with minimum distance to the corner analysis on ROC curves. Results: The distribution of patients with Lisfranc instability was 58% female with an average age of 38.5±17.6 years. Of the Lisfranc injuries, 36% were purely ligamentous, 18% demonstrated an avulsion injury, and 43% involved a metatarsal base fracture. In the Lisfranc cohort, the median percent difference between injured and uninjured feet was 28.2% (IQR: 20.9%) for volume, 36.3% (IQR: 31.1%) for C1-M2 area, and 40.0% (IQR: 23.3%) for C1-M2 diastasis. Mann-Whitney testing was significant for percent difference between left and right feet for Lisfranc patients versus patients with an uninjured midfoot (p < 0.001). The area under the curve and associated diagnostic cutoffs for Lisfranc instability, were 0.81 and 18% for volume, 0.84 and 20% for area, and 0.91 and 28% for diastasis (Figure 1). Conclusion: Diastasis (1D), area (2D), and volume (3D) measurements are effective measurements to diagnose Lisfranc instability on WBCT. With current diagnostic algorithms, however, 1D measurements afford superior diagnostic sensitivity as compared to 2D and 3D measurements when using WBCT, suggesting Lisfranc instability may be best appreciated in the axial plane. Additional studies are necessary to expand the sample population to assess for corroboration with the current results, especially for subtle Lisfranc instability

Epidemiology, Pathoanatomy and Clinicoradiologic Correlations of Quadrimalleolar Ankle Fractures: A Cross-Sectional Study

Category: Ankle; Trauma Introduction/Purpose: The term ‘quadrimalleolar fracture’ (QMF) describes a trimalleolar (TM) ankle fracture with an associated Chaput or Wagstaffe fracture. Optimal fixation of these injuries not only allows for bone-to-bone healing but also facilitates syndesmotic reduction. However, this is a relatively new concept, and the literature on QMFs is limited to a few case series. Hence, we conducted this study to determine the epidemiology, patterns, and clinicoradiologic correlations of QMFs. The primary objective of this study was to describe the prevalence and patterns of QMFs. The secondary objective was to determine if certain clinical or radiological parameters were associated with different types and patterns of QMFs. Methods: A retrospective analysis of ankle fractures presenting to three tertiary referral hospitals was undertaken. Adult patients (≥18 years) presenting with an acute, traumatic TM ankle fracture over 3 years (July 2018 to July 2021) were included. Isolated medial and lateral malleolar fractures, bimalleolar ankle fractures, pediatric patients, pilon fractures, pathological fractures, and those with delayed presentation or (≥3 weeks of injury) were excluded. Clinical demographic variables were obtained from the patients’ medical records. AP, lateral, and mortise ankle radiographs, and CT scans, (axial, coronal, and sagittal sections along with 3D volume reconstructed models) whenever available, were evaluated in detail. Demographics and radiological parameters were compared between TM and QMF, as well as between different types of QMFs. Odds ratios with 95% confidence intervals were determined to test the strength of association. Results: A total of 876 adult patients with ankle fractures were included after the screening, of which 323 had a TM ankle fracture for which a CT scan had been performed. A total of 159 AITFL avulsions were identified, yielding a prevalence of 18.2% amongst all ankle fractures and 26.1% in ankle fractures where a CT scan had been performed. TMFs had the significantly highest proportion of CT-confirmed AITFL avulsions (44.4%) in comparison to unimalleolar (4.4%) and bimalleolar fractures (6.4%) (P < 0.0001). Age and osteoporosis were significant associations of QMFs. Avulsion of the medial malleolus, Weber B fibular fracture, and supination external rotation mechanism were significantly associated with Wagstaffe fractures. Size of the Chaput fracture was inversely related to that of the posterior malleolar fracture. Conclusion: Quadrimalleolar ankle fractures account for a significant proportion of ankle fractures. The strengths of this study include a large sample size, which was derived from three different hospitals, consecutive inclusion (or exclusion) of cases, strict adherence to the STROBE guidelines, and the fact that only CT-confirmed cases were used to determine clinic-radiological associations. Wagstaffe and Chaput fractures have distinct clinical and radiological correlations. However, further research is needed to determine the optimal fixation protocols for these injuries

A Novel Ultrasonographic Method to Detect Intra-Operative Syndesmotic Malreduction – the “Gap Penetrance” Sign

Category: Ankle; Other Introduction/Purpose: Anatomical reduction of the distal syndesmosis can be challenging. There is ongoing debate and variability in the methods used for evaluating the accuracy of reduction, including radiography, intra-operative CT, arthroscopy, and direct visualization. Tornetta et al. have described a method called ‘the articular surface method’ that evaluates the relationship between the articular cartilage of the distal anteromedial fibula and the anterolateral tibia as being significantly more accurate for detecting malreduction. However, it entails an additional surgical incision over the distal aspect of the ankle. The aim of this study was to find a non-invasive method using ultrasound to assess the accuracy of reduction in syndesmotic injuries. Methods: A cadaveric syndesmotic instability model was created by dissecting the PITFL, IOL, and AITFL through a small posterior incision. The fibula was fixed in incremental degrees of rotational malreduction to achieve a malreduction of 3, 5, and 7 mm. A blinded observer assessed the syndesmosis using a portable ultrasound device. The probe was placed in its short axis at the level of the ankle joint then moved proximally until both the anteromedial fibular and anterolateral tibial articular surfaces were visualized simultaneously in one view. In a reduced syndesmosis, the distal articular surfaces of the tibia and fibula overlap. This relationship is altered in a malreduced syndesmosis, which allows ultrasonographic waves to ‘penetrate’ through the malreduced articular surfaces and be readily detected. This sign was graded positive if an acoustic signal penetrated between the distal articular surfaces of the tibia and fibula, and negative if no acoustic signal was detected. Results: The gap penetrance sign was positive in all 3 instances of malreduced syndesmoses, and negative in an anatomically reduced syndesmosis. Figure 1 illustrates the outcomes in a reduced syndesmosis and malreduced syndesmosis, respectively. Conclusion: We introduced a novel sign that can be used as a surrogate of the ‘articular surface method’ to detect syndesmotic malreduction. It is accurate, can obviate the need for a separate surgical incision for direct visualization, permits rapid point-of- care evaluation in the operating room, and minimizes radiation exposur

3D Weightbearing CT for the Diagnosis of Lisfranc Instability: An Update

Category: Midfoot/Forefoot; Other Introduction/Purpose: Lisfranc instability is often a challenging injury to diagnose, with up to one-third being missed on initial evaluation. Lisfranc instability is assessed by widening of the space between the second metatarsal base and the medial cuneiform. This space is visualized on X-Ray; however, in subtle Lisfranc instability cases computed tomography (CT) imaging is often obtained. Given the 1D nature of diastasis measurement, X-ray should be an adequate means of evaluating this widening, yet clinical practice suggests weightbearing CT (WBCT) is more sensitive. This suggests the 3D location of the diastasis measurement is crucial. This study aimed to first compare weight-bearing X-ray and WBCT diastasis and area measurements of the Lisfranc complex, and second to compare WBCT diastasis measurements at various locations in the coronal plane. Methods: A total of 90 patients with both weight-bearing foot X-ray and bilateral foot WBCT were included: 37 patients had confirmed Lisfranc instability, and 53 patients had no history of midfoot injury. Lisfranc instability was confirmed intraoperatively or by clinical examination performed by the surgeon. For all 90 patients, the interosseous diastasis and area between the medial cortex of the second metatarsal and the lateral cortex of the medial cuneiform were measured on both weightbearing X-ray and axial slices of WBCT. For a subset of patients (12 in each cohort) the diastasis between second metatarsal and medial cuneiform was measured at 4 distinct axial locations using coronal slices of the WBCT (Figure 1). Results: A Wilcoxon test comparison of diastasis and area measurements on weightbearing X-ray and axial slices of WBCT revealed a significant difference in the weightbearing X-ray and WBCT measurements (p < 0.001) for both the control and Lisfranc cohorts. A comparison of weightbearing X-ray diastasis to dorsal, interosseous, and plantar diastasis measurements on coronal slices using Kruskal Willis analysis for the control cohort revealed a significant difference in all three measurements (Figure 1, p-values listed). Kruskal Willis analysis of the Lisfranc cohort demonstrated a significant difference between the X-ray diastasis and the plantar WBCT diastasis (p=0.01), but no difference from interosseous (p=0.08) or dorsal (p=0.33) diastases. A comparison of the axial WBCT diastasis measurements compared to the three coronal diastasis measurements revealed no difference in either cohort. Conclusion: Our results showed that for assessing the Lisfranc joint in subtle cases and healthy individuals, WBCT remains the most accurate imaging tool. However, in patients with confirmed Lisfranc instability, X-ray measurements are more reliable if the instability is at the dorsal and interosseous levels and not the plantar level. Hence, to assess the Lisfranc joint at different levels, WBCT has superiority over X-ray. Additionally, the axial diastasis of the Lisfranc joint on WBCT seems similar to coronal diastasis rendering both views reliable for measurements

Role of Insole Material in Treatment of Plantar Fasciitis: A Randomized Clinical Trial

Category: Hindfoot; Other Introduction/Purpose: Plantar fasciitis (PF), a leading cause of persistent heel pain, results in almost a million physician visits annually. Conservative treatment is often the first line of management with insoles being frequently prescribed. While multiple studies have compared insoles based on the degree of customization to foot contour, the literature is lacking in data comparing insoles based on their material. In this randomized clinical trial, we compared the early effects of foam, polyurethane, and carbon fiber insoles in the treatment of PF, using a robust set of PROMS. Methods: A randomized clinical trial was designed at the foot and ankle research center of a tertiary care hospital in Massachusetts. Adult patients diagnosed with PF who had not received injectable or surgical treatment for it were included. Participants who consented were randomly allocated one of the three prefabricated insoles – carbon fiber insole (Group 1, n=13), polyurethane insole (Group 2, n=13), or foam insole (Group 3, n=9) for regular use. Their response was recorded using PROMIS 3a (for pain intensity), PROMIS 4a (for pain interference), FAOS (Foot and Ankle Outcome Score), and VAS for pain at baseline (T0), two (T2), six (T6) and twelve weeks (T12). A per-proto analysis was undertaken using Kruskal Wallis and Friedman tests. P0.05 for both). The group-wise distribution of participants based on sex and laterality of the affected foot showed no difference. Participants in each group reported similar intensity of the pain (VAS) at baseline and at all follow-up time points (p>0.05). A comparison of outcomes between baseline and subsequent timepoints showed significant improvement in quality of life (FAOS) at T12 (p=0.047) for carbon fibre insole users (Figure 1), significant pain relief on PROMIS Pain intensity and Pain Interference questionnaires for foam insoles at T3 and T12 (p=0.0003, 0.036 respectively). Conclusion: Carbon fiber insoles offered slightly better pain relief as early as six weeks into treatment and improved quality of life after twelve weeks of use. A possible link between the material of insole used and effective treatment of PF may exist. Conducting further analyses on the position of the foot during gait while using insoles and designing the insoles based on patient-specific criteria should be considered for future research

Three-Dimensional Mapping of Chaput Tubercle Fractures: Evaluation of Morphologic Characteristics and Anterior Inferior Tibiofibular Ligament Involvement

Category: Ankle; Trauma Introduction/Purpose: Chaput tubercle fractures, which are thought to represent tibial-sided avulsions of the anterior inferior tibiofibular ligament (AITFL), are prevalent in up to 30% of trimalleolar ankle fractures. The optimal treatment of small Chaput avulsions is debatable; direct fixation with suture anchor devices and indirect (syndesmotic) fixation are considered as viable options, with proponents on both sides. Moreover, recent literature highlights the potential anatomical alterations to the incisura tibialis resulting from malreduction of large Chaput fragments, furthering the case for direct fixation. Hence, we performed a CT- based three-dimensional fracture mapping study to identify the morphological characteristics of these fractures, and to determine whether they consistently involve the AITFL, tibial plafond and incisura tibialis. Methods: This study included adult patients who had an ankle fracture with a Chaput component; the scheme described by Rammelt et al. was used to classify these fractures. CT scans were obtained, and 3D models were generated. The models were superimposed over a statistical shape model of the right tibia which served as a template and fracture lines were marked. The footprints of proximal and main bands of the AITFL and Basset’s ligament were also marked on the template tibia. The tibial template along with the fracture lines was then imported into MATLAB, and an automated script was used to determine the fragment size (length, breadth, and height), fracture surface area, involvement of the tibial plafond, tibial incisura, and the anterior inferior tibiofibular ligament (AITFL) and Basset’s ligament. Fracture maps and heat maps were generated. Agglomerative cluster analysis using Ward’s linkage was used to identify discrete fracture categories. Results: 76 patients, 21 males and 55 females were included in this study. Cluster analysis identified two distinct groups of fractures, each with two unique subgroups. We present this as a modification of the existing classification system. The first group, corresponded to Rammelt Type 1 fractures (sub centimetric extra-articular avulsion fractures, n=47). Of these, 19% (n=9) did not involve the AITFL, which we termed as Type 1a, and 91% (n=48) involved the AITFL, which we termed as Type 1b. The second group consisted of large intra-articular fractures that corresponded to Rammelt Type 2 injuries. Of these 23% (n=6) involved only the incisura, which we termed as Type 2a; 77 % involved both the incisura and the tibial plafond and were termed as Type 2b. Conclusion: We propose a modification of the existing classification of Chaput fractures on the basis of quantitative fracture mapping. This study provides new insights into the morphological characteristics of Chaput fractures. 19% of small Chaput fractures do not involve the AITFL and may not require direct fixation. Conversely, all large-sized fragments involve the incisura and necessitate anatomical reduction to achieve accurate syndesmotic reduction. Our proposed modification can aid in surgical decision-making, particularly in choosing between direct and indirect syndesmotic fixation