Informed consent was waived and approved by the human subjects review board for initial retrospective review of charts dated between September 2013 and June 2017 of all patients who had USGT for elbow tendons (common flexor and common extensor), patellar tendon, Achilles tendon (midportion and insertional), and plantar fascia. Review found a total of 262 patients (N = 87 elbow; N = 38 patellar; N = 23 midportion Achilles; N = 34 insertional Achilles; N = 80 plantar fascia). Some patients had more than one procedure performed during the study period making for a total of 289 procedures.
Data on complications were included from contact with the patient at any time point between date of procedure and long-term follow-up. Complication screening included infection, tendon rupture, hypersensitivity, or other as reported by the patient. Outcomes assessing pain and quality of life were assessed at baseline prior to the procedure, short-term follow up (6 weeks or 12 weeks), and long-term follow up (median 1.7 to 3.6 years depending on location). Short-term follow up data was gathered in clinic, while long-term follow up data was collected through online survey or phone survey which was also approved by the human subjects review board. Pilot testing for long-term follow-up was performed with the insertional AT group (14). Based on our high survey completion rate and lack of information about quality of life, the SF-12 was added for the other sites to the long-term follow-up assessment.
Pain assessments varied by tendinopathy type depending on region-specific questionnaires. Pain was assessed for the patellar group on a 4-point scale modified from the Kujala scale: None, Slight and Occasional, Occasionally Severe, and Severe/Almost always present. Pain was assessed for the midportion Achilles, insertional Achilles, and plantar fascia groups on a 4-point scale from the American Orthopedic Foot and Ankle Score (AOFAS): None, Mild/Occasional, Moderate/Daily, and Severe/Constant. For the elbow tendon group (common flexor tendon and common extensor tendon), pain was assessed on a 4-point scale adopted from the Mayo Performance Scale: None, Mild/Occasional, Moderate/Daily, and Severe/Constant.
For all patients, quality of life was assessed using the Physical Component Summary (PCS) and Mental Component Summary (MCS) of the Short-Form 12-Item Survey (SF-12) (15). The SF-12 compares the study sample to the general population with t scores (mean 50; standard deviation 10).
Patient satisfaction at short term follow up was on a 5-point scale from Very satisfied (1) to Very dissatisfied (5). Patients were asked about any procedure-related complications at routine follow-up clinic visits (2-weeks, 6-weeks, 12-weeks). In addition, participants were asked to report any procedure-related complications at long-term follow-up via phone/email.
Procedure Description
General
All patients underwent a thorough clinical evaluation including a diagnostic ultrasound. Those with chronic clinical symptoms (> 3 months) and ultrasound findings amendable to treatment with USGT (regions of degenerative or calcified tissue) were indicated for the procedure. Mean duration of symptoms prior to procedure was calculated based on number of patients who responded: 15 months for patellar, 38.9 months for non-insertional Achilles, 26 months for insertional Achilles, 31 months for plantar fascia, and 22 months for elbow. Other treatment options were discussed with patients including physical therapy, injections, extracorporeal shockwave therapy, and traditional surgical approaches. However, most patients had failed multiple prior treatments including formal physical therapy (elbow: 49, patellar: 12, midportion Achilles: 17, insertional Achilles: 22, plantar fascia: 40) and cortisone injections (elbow: 47, patellar: 2, midportion Achilles: 2, insertional Achilles: 5, plantar fascia: 41).
All procedures were performed by the senior author (MMH) who is a sports medicine physician with fellowship training in diagnostic musculoskeletal and sports ultrasound and ultrasound guided procedures. The procedures were performed in an outpatient clinical procedure suite using sterile technique including sterile ultrasound transducer covers and sterile acoustic coupling gel. Live continuous ultrasound guidance was used throughout the procedures with either an iU22 or EPIQ ultrasound cart (Philips Healthcare, Bothell, WA) and a high frequency linear transducer (12 − 5 or 18 − 5 MHz). Anesthesia was achieved with local infiltration of either 1% lidocaine without epinephrine or a 50:50 mixture of 1% lidocaine without epinephrine and 0.5% ropivacaine. Between 5 and 10 mL of local anesthetic was used based on location and patient comfort. No one required sedation. A #11 blade was used to make an approximately 5 mm skin incision and create a tract to the tendon/fascia. This was always performed in-line with the tendon/fascia to avoid iatrogenic horizontal laceration of the fibers. The TX 1 or TX 2 device (Tenex Health, Lake Forest, CA) was then used to perform all tenotomy and debridement procedures. The TX 1 and TX 2 devices operate in an identical fashion utilizing ultrasound energy to cut and debride tissue while allowing for local saline irrigation and aspiration of the debrided tissue. Differences in the two devices include only length and external fabrication (plastic vs metal sheath). All procedures aimed to debride regions of degenerative or calcific tissue with special considerations at each location as detailed below.
The post-procedure protocol was individualized based on location and extent of pathology and desired functional demands. However, our general approach was 2 weeks of rest and then progressive rehabilitation. Pain free active range of motion was started on post-procedure day 1 for all procedure sites. Following treatment of the plantar fascia or Achilles tendon, patients could weight bear as tolerated, but a protective walking boot was used for the first 1–2 weeks. Partial weight bearing on crutches or full weight bearing in a knee immobilizer was prescribed for 1–2 weeks following patellar tendon debridement. All elbow patients had a 5-pound lifting restriction for the first 6 weeks. The soonest anyone could return to full activity was 6 weeks; however, most patients returning to sports activity or manual labor required 12 weeks prior to full clearance. Near the end of our study period a criterion-based rehabilitation protocol was adopted based on our experience (Tables 1,2).
Table 1
Criterion Based Rehabilitation Progression Following Ultrasound Guided Tendon Debridement of the Upper Limb
Rehabilitation Phase | Estimated Timeline† | Special considerations | Restrictions | Goals | Functional test to progress to next phase |
1 | 0–2 weeks | Early ROM encouraged starting day after procedure | 1. Sling use only as needed for initial pain control 2. No lifting > 5 lbs 3. Limit repetitive use | 1. Control swelling 2. Restore ROM 3. Muscle activation | 1. Pain free elbow and shoulder ROM |
2 | 2–6 weeks | Pain < 3/10 with all activities | 1. No lifting > 5 lbs | 1. Neuromuscular control 2. Proprioception 3. Gentle muscular strengthening | 1. 5 lb lateral raise with elbow extended |
3 | 6 + weeks | N/A | 1. Monitor load progression‡ | 1. Progressive strengthening 2. Sport/region specific RTP preparation | 1. Symmetric grip strength 2. 5 push- ups (standard or knee supported) |
4 | 12 + weeks | Not applicable for all patients | N/A | 1. Full unrestricted return to sport/work 2. Transition to maintenance program (S&C, personal trainer, self-directed HEP) | 1. Specific to demands of sport/position 2. Guided by AT and S&C staff |
NWB, Non-weight-bearing; ROM, Range of motion; PWB, Partial weight-bearing; WBAT, Weight-bearing as tolerated; RTP Return to play; AT, Athletic trainer; S&C, Strength and conditioning; HEP, Home exercise program † To be used as a general guide based on biologic tissue healing. This timeline does not consider the location and extent of diseased tissue as well as other intrinsic patient factors that may impact time to clinical healing. ‡ Basic load progression principles: Pain level < 3/10 with activity. Any pain associated with the activity should not persist into the following day. If pain persists then load needs to be decreased. |
Elbow
A detailed description of our technique at the elbow has been previously reported (9). When treating the common extensor tendon, the patient was placed in a supine position with the head of the table raised approximately 30 degrees. The elbow was in slight flexion with the forearm pronated and resting on the table. A distal to proximal approach was used. Care was taken to avoid the radial collateral ligament during both the incision and the debridement with the TX device as to not inadvertently destabilize the elbow.
The common flexor/pronator tendon was approached with the patient in a supine or side lying position with the elbow in extension and forearm supinated. The location of the ulnar nerve was confirmed and carefully monitored throughout the procedure with ultrasound. Keeping the elbow in relative extension provided additional protection to the nerve in cases of subtle instability. A similar distal to proximal approach was used.
Patellar Tendon
Patients were in a supine position with the knee flexed to approximately 30 degrees and supported on a pillow. Two separate techniques were used depending on the location and extent of pathology. A more standard distal to proximal approach allowed for debridement of the patellar attachment but required division of the superficial tendon fibers for introduction of the TX device (Fig. 1). When the region of pathology predominately involved the deep fibers with posteriorly projecting nodularity into Hoffa’s fat pad, a lateral to medial approach was taken (Fig. 2). This allowed for more complete debridement of the involved tendon and limited debridement of the fat pad which typically becomes adherent to the region of tendinosis in these cases. The superficial fibers were completely spared with this second technique. Care was taken to avoid injury to the healthy portion of the tendon during the incision given the change to a short axis image of the tendon. The scalpel blade was maintained in an orientation longitudinal to the tendon fibers to further avoid potential for horizontal laceration.
Achilles Tendon
Patients were positioned prone with feet hanging free off the edge of the table to allow access to either the midportion or insertion of the Achilles tendon. We have previously published our technique for debridement of the Achilles insertion (14). Midportion pathology was addressed in a similar manner with a distal to proximal approach with both scalpel and device introduced in the longitudinal axis of the tendon. The location of the sural nerve was confirmed prior to incision in all cases.
Plantar Fascia
Patient positioning was identical to the Achilles. Pre-procedure ultrasound imaging identified the medial calcaneal sensory nerve and lateral plantar nerve prior to incision. A medial approach was taken to the central cord origin. If there was concomitant lateral cord origin involvement, the TX device was advanced to this location from the medial side. In only rare cases of isolated lateral cord involvement was a lateral approach taken. If a lateral approach was considered, the location of the sural nerve was confirmed during the pre-procedural ultrasound imaging.
Analysis
Descriptive statistics were used to report patient satisfaction and complications (type, frequency) by site. In order to minimize sample bias and maximize the inclusion of all patients identified in the retrospective review, data on patient satisfaction and complication rate were included from any time point. Descriptive statistics were also used to report sample characteristics by group (tendinopathy/fasciopathy site). Non-parametric and parametric tests (Wilcoxon Signed Rank test for pain as a categorical variable; Paired t-test for quality of life as a continuous variable) were used to compare outcomes at baseline (prior to USGT) to follow-up (short-term or long-term). Only a single side per patient was used for analysis in the 27 patients who had USGT on both sides to fulfill the assumption of independence of observations. Due to high rates of missing data, we chose not to impute data for missing values in the statistical analysis. Patient reported outcomes in tables reflect all available responses at each time point and analyses of change reflect all available pairs for comparison between time points. Statistical significance was defined by p ≤ 0.05.