Abstract
Surgical arthrolysis is recommended for patients who suffer from stiff elbow and desire to restore near-normal range of motion and better joint function. Arthroscopic arthrolysis has shown significant advantages over open surgery; however, the close proximity of nerves and blood vessels, along with the limited operating space, presents challenges in performing arthroscopic procedures, and paralysis and injury of the ulnar nerve are frequently encountered. We adopt an arthroscopic posterior medial dual portals technique to expose and protect the ulnar nerve, followed by medial gutter and posterior compartment debridement utilizing an outside-in approach for the stiff elbow. Arthroscopically exposing the ulnar nerve and debriding under viewing via the posterior medial dual portals has the advantages of easier identification of lesions and more comprehensive debridement, reduced postoperative scarring and pain, faster postoperative return to life and work, and reduced risk of neurovascular injury.
Technique Video
Stiff elbow is generally defined as a range of flexion-extension less than 100° and/or flexion contracture greater than 30°, with 50° of flexion and extension restriction causing up to 80% of daily activities to be restricted.1, 2, 3 Whether it is extrinsic, intrinsic, posttraumatic, or nontraumatic stiff elbows, surgical arthrolysis is recommended for patients who desire to restore near-normal range of motion and better joint function. Arthroscopic arthrolysis has shown significant advantages over open surgery,4, 5, 6 but the close proximity of nerves and blood vessels and the narrow subcutaneous operating space make arthroscopic surgery challenging,7 with paralysis and injury of the ulnar nerve frequently encountered.3,8,9 We adopt a posterior medial dual approach arthroscopic technique to clean the medial gutter and posterior compartment from the outside to the inside for the treatment of stiff elbow.
Surgical Technique
The surgical technique is presented in Video 1. The studies involving human participants were reviewed and approved by Ethics Review Form for the Branch for Medical Research and Clinical Technology Application, Ethics Committee of Luoyang Orthopedic Hospital of Henan Province (2024XJS0009-01). The patients/participants provided their written informed consent to participate in this study.
Indications and Preoperative Planning
The procedure is appropriate in the following situations: stiffness of the elbow impacting daily activities and quality of life over 6 months; confirmation of the presence of elbow joint space on radiographs or computed tomography scans; the ulnar nerve is palpable in the ulnar nerve groove. Patients with stiff elbow and mild ulnar neuritis who do not require anterior transposition can be treated with the technique described in this article. In cases with history of medial elbow open injury or prior surgery, the patients may benefit from open ulnar nerve neurolysis through an incision of about 3 cm given its ease and lower complication rates.
Preoperative ultrasound is used to confirm the ulnar nerve course, nerve compression, nerve shape, and so on, and to rule out ulnar nerve instability or snapping medial triceps. Preoperative 3-dimensional (3D) computed tomography reconstruction of the elbow is applied to make the preoperative plan.
Patient Positioning and Setup
After general anesthesia or brachial plexus anesthesia, the patient is placed in a lateral decubitus position, with a tourniquet tied at root of the affected arm. The affected arm is secured on an arm holder to allow elbow flexion and extension. According to the principle of aseptic operation, the upper limb is disinfected and draped, and sterile bandages are used to wrap the forearm to prevent swelling.4 The tourniquet is inflated to 250 mm Hg after exsanguination, and the ischemic time is less than 90 minutes. The medial epicondyle, olecranon, and ulnar nerve are outlined, the posteromedial double portal that runs along the ulnar nerve course at a distance of 2.5 cm above and below the medial epicondyle is marked, and the posterolateral portal is located and marked at the cross of the lateral border of olecranon and the transverse level of the proximal medial epicondyle (Fig 1).
Fig 1.
Illustration of the landmarks and portals in a right elbow case. An unsterilized pneumatic tourniquet is applied to the root of the affected upper arm while the patient is positioned in lateral decubitus. The proximal one-third of the upper arm, along with the tourniquet, is securely supported on a padded arm holder. The olecranon (OL) and medial epicondyle (ME) are delineated, and the proximal posteromedial portal (PPM) and the distal posteromedial portal (DPM) are located 2.5 cm above and below the medial epicondyle along the course of the ulnar nerve (black dotted line). The posterolateral portal (PL) is placed at the intersection of the lateral border of the olecranon (longitudinal white dotted line) and the corresponding transverse level line of the proximal medial epicondyle (transverse white dotted line). (D, distal; M, medial; L, lateral; P, proximal.)
Arthroscopic Extra-Articular Ulnar Nerve Exposure
After the creation of a preliminary subcutaneous working space through blunt dissection via the posteromedial dual portals, a standard 4-mm 30° arthroscope and a shaver (Bone Cutter; Arthrex, Naples, FL) are introduced separately to expand this working space further (Fig 2). By viewing from the proximal portal, a radiofrequency device (RD) (COOLPULSE 90 Electrode; DePuy Mitek, Raynham, MA) is inserted through the distal portal and advanced proximally to expose and release the ulnar nerve from the adjacent triceps muscle; tissue covering the ulnar nerve is resected using a shaver, thereby distally revealing the cubital tunnel retinaculum. The viewing portal and working portal are then switched; by observing from the distal portal, a RD probe is introduced through the proximal portal; the cubital tunnel retinaculum overlying the ulnar nerve is transected in a proximal to distal direction; and the underlying ulnar nerve is isolated from surrounding tissues (Fig 3). To avoid injuring the ulnar nerve, the RD probe, the shaver blade, and the burr are visualized during the procedure; vacuum suction around the RD is continuous throughout the procedure.5
Fig 2.
Creation of posteromedial 2 portals and subcutaneous working space in the right elbow case. The preliminary subcutaneous space is established by gently sweeping with a blunt-tip trocar and a blunt switching stick through the 2 posteromedial portals. The arthroscope (red arrowhead) and the shaver (white arrowhead) is introduced separately through these 2 posteromedial portals to expand the subcutaneous working space further. (D, distal; M, medial; L, lateral; P, proximal)
Fig 3.
The exposure and release of the proximal and mid segments of the ulnar nerve from the triceps in the right elbow case. (A, B) Observing through the proximal portal with the arthroscope angled distally, a radiofrequency device is introduced via the distal portal and advanced proximally to expose and liberate the ulnar nerve from the adjacent triceps muscle. (C, D) With the arthroscope tilted proximally, the mid segment of ulnar nerve is exposed and released from the triceps muscle. (E, F) The viewing portal and working portal are switched; by observing from the distal portal, the radiofrequency device is introduced through the proximal portal; and the cubital tunnel retinaculum (curved dotted line) overlying the ulnar nerve is transected in a proximal to distal direction. (G, H) The underlying ulnar nerve is isolated from adjacent tissues, and the bone (BO) beneath the medial capsule is exposed with the radiofrequency device. (AS, arthroscope; D, distal; L, lateral; M, medial; P, proximal; RD, radiofrequency device; TM, triceps muscle; UN, ulnar nerve.)
Outside-In Medial Gutter and Posterior Compartment Debridement
The tissue lateral to the ulnar nerve, including portions of the medial capsule, is removed utilizing RD. With continued switching between portals, the arthroscope is reinserted through the proximal portal while reinserting the RD via the distal portal to resect additional posterolateral elbow capsule tissue and expose the medial ulnohumeral joint by elbow flexion-extension (Fig 4). The elbow is extended and, using the outside-in-out technique, the switching stick is inserted from the distal posteromedial portal into and passed through the posterior compartment, penetrating through and out of the proximal posterolateral skin. The switching stick is then retreated laterally with its end tenting the triceps and the posterior compartment capsule to serve as a retractor (Fig 5). The posteromedial capsule is stripped off from the humerus and the olecranon, and any remnant portion of the ulnar collateral ligament is resected. Osteophytic overgrowth on the medial olecranon is trimmed using a round burr, followed by removal of the posterior compartment capsule with a shaver via the distal posteromedial portal. At this stage the outside-in medial gutter and posteromedial capsule debridement is finished (Fig 6).
Fig 4.
The exposure of ulnohumeral joint in the right elbow case. (A, B) By observing from the proximal portal with the arthroscope (AS) angled proximally, the radiofrequency device (RD) is introduced via the distal portal to excise tissue lateral to the ulnar nerve. The residual medial capsule (white dotted line) is exposed, and the medial rim of the trochlea and the capsule between the trochlea (TR) and medial olecranon (OL) are confirmed by elbow flexion-extension. (C, D) After resection of the residual medial capsule, the triceps muscle (TM) is elevated using the RD to expose the ulnohumeral joint space. (D, distal; L, lateral; M, medial; P, proximal.)
Fig 5.
The insertion and utilization of posterior compartment retractor. (A, B) Observing from the proximal portal, the switching stick is inserted via the distal posteromedial portal into and passed through the posterior compartment, penetrating through and out of the proximal posterolateral skin. (C, D) The ulnar nerve (UN) is checked to prevent any nerve irritation caused by the switching stick. (E, F) The switching stick is then retreated laterally with its end tenting the posterior compartment capsule (PCC) to serve as a retractor, thereby establishing a working space within the posterior compartment and facilitating excision of the tensioned capsule with a radiofrequency device (RD). (D, distal; L, lateral; M, medial; P, proximal; SS, switching stick [white arrowhead], TM, triceps muscle.)
Fig 6.
Medial gutter and posterior compartment debridement is performed through the distal posteromedial portal, with visualization provided through the proximal posteromedial portal in the right elbow. (A) Observing from the proximal posteromedial portal, a radiofrequency device is introduced via the distal posteromedial portal to resect the posteromedial capsule (PMC) while it is being tensioned by a switching stick (SS) retractor. (B) The posterolateral capsule (PLC) surrounding the SS is carefully peeled away from the lateral humeral column to reveal any osteophyte and loose body in the olecranon fossa. (C) The posterior compartment capsule (PCC) is resected using a shaver inserted through distal posteromedial portal. (D) The residual portion of the posteromedial capsule (posterior band of the medial collateral ligament [white dotted line]), which connects the trochlea (TR) and olecranon (OL), is resected utilizing a radiofrequency device introduced from the distal posteromedial portal. (E, F) The remaining section of the posteromedial capsule on the olecranon is removed to expose osteophytic overgrowth at its posterior medial corner (PMC), which is subsequently trimmed using a burr. (D, distal; L, lateral; M, medial; OS, osteophytes; P, proximal; RD, radiofrequency device.)
By visualizing from the proximal posteromedial portal, the posterolateral portal is located with a spinal needle and established using the outside-in technique. The posterolateral capsule is then carefully stripped away and resected from both the humerus and the olecranon. The spinal needle is inserted transcutaneously to retract the ulnar nerve medially, with its tip penetrating the medial intermuscular septum to create a fixed retraction medially for the ulnar nerve. The osteophyte and loose body in the olecranon fossa are removed using the round burr. The posterolateral capsule is removed, and the tip of the olecranon and its lateral corner are then exposed, followed by trimming the residual osteophytic overgrowth with the burr (Fig 7). The arthroscope is subsequently switched to the distal posteromedial portal, allowing for reevaluation of the debridement completion or further plasty of the posterior compartment. Additionally, the integrity of the ulnar nerve is reconfirmed by turning the arthroscope medially (Fig 8). After the completion of posterior compartment debridement, the procedure continues with debridement of both the posterolateral and anterior compartments.
Fig 7.
Posterior compartment debridement is performed through the posterolateral portal, with visualization from the proximal posteromedial portal in the right elbow. (A) Observing from the proximal posteromedial portal, a radiofrequency device is introduced via the posterolateral portal to excise the synovium of the posterior compartment. (B) The capsule is carefully peeled away from the posterolateral corner (PLC) of the olecranon (OL) to expose any osteophyte. (C) The posterolateral capsule is resected using a shaver. (D) A spinal needle (SN) is percutaneously inserted lateral to the ulnar nerve to retract it medially; this needle also penetrates into the medial interosseous membrane, creating a fixed retractor for protection of the ulnar nerve. (E, F) The osteophyte in the olecranon fossa is removed with the burr introduced via the posterolateral portal, and the osteophytic overgrowth of the olecranon tip and the posterolateral corner are trimmed with the burr. (D, distal; L, lateral; M, medial; P, proximal; OS, osteophyte; RD, radiofrequency device; UN, ulnar nerve.)
Fig 8.
Viewing from the distal posteromedial portal in the right elbow case. (A) The viewing portal is switched to distal posteromedial portal, the ulnar nerve (UN) being retracted by the spinal needle (SN) is reassessed, while a radiofrequency device (RD) is introduced via the posterolateral portal to remove any residual tissue. (B) Through observation from the distal posteromedial portal, a burr is introduced via the posterolateral portal to remove any residual osteophytes in the olecranon fossa (OF). (D, distal; L, lateral; M, medial; P, proximal.)
Postoperative Protocol
The patient is treated with a compressive bandage and a standard sling, which is removed the day after surgery. Active-assisted and passive rehabilitation exercises of the elbow start immediately after surgery. The duration and intensity of exercise gradually increase according to the patient’s tolerance. Pearls and pitfalls of our arthroscopic technique are outlined in Table 1.
Table 1.
Pearls and Pitfalls
| Pearls |
| Preoperative ultrasound could be applied to rule out ulnar nerve instability or snapping medial triceps. |
| Preoperative 3D CT scan is helpful for planning, particularly in assessing and trimming osteophytic overgrowth. |
| To avoid ulnar nerve injury, the RD probe, the shaver blade, and the burr should be visualized and facing away from the ulnar nerve during the procedure. |
| Continuous vacuum suction around the RD should be maintained throughout the procedure. |
| A spinal needle is employed to create a fixed retractor for positioning the ulnar nerve away from the working area of plasty. |
| The switching stick serves as an effective posterior compartment retractor, facilitating debridement of the capsule. |
| The distal posteromedial portal can be used to debride the soft tissue and trim the osteophyte in the medial gutter. |
| The posterolateral portal can be employed to debride posterolateral tissues and perform the olecranon tip and fossa plasty. |
| Visualization of both posterolateral capsule and posterolateral osteophytic overgrowth of the olecranon is achievable only through an arthroscope inserted via the proximal posteromedial portal. |
| Pitfalls |
| For cases involving ulnar nerve instability, the ulnar nerve may dislocate anteriorly to the medial epicondyle during elbow flexion. Consequently, procedures aimed at creating a subcutaneous working space could increase the risk of nerve injury. |
| For patients with previous surgical operations of medial elbow, the structures adjacent to the ulnar nerve can become distorted, therefore the technique illustrated in this procedure is not suitable for these patients. |
| The use of a RD probe and shaver blade poses a risk of iatrogenic injury to the ulnar nerve if these instruments are out of sight. Additionally, blocked suction of the RD probe may result in thermal damage to the ulnar nerve. |
3D, 3-dimensional; CT, computed tomography; RD, radiofrequency device.
Discussion
The advantages of our technique are outlined in Table 2. First, the entire operation is performed under arthroscopy, ensuring that the shaver and the RD blade always face away from the ulnar nerve, thereby enhancing safety for this critical structure. Second, adopting an outside-in technique leverages the anatomical characteristics of the elbow joint to access the medial gutter and posterior compartment effectively and precisely. Finally, minimally invasive incision and operation can help patients return to regular activities of daily life as soon as possible.
Table 2.
Advantages and Disadvantages
| Advantages |
| Easier identification of lesions and more comprehensive debridement for the posterior compartment and the medial gutter. |
| Reduced postoperative scarring and pain, faster postoperative return to life and work, and decreased neurovascular injury risk. |
| Disadvantages |
| The high cost of arthroscopic equipment and the long learning curve of doctors. |
| Compared with open surgery, arthroscopic surgery takes longer preparation time. |
| Persistent fluid extravasation in the portals. |
Numerous studies have described the use of arthroscopic ulnar nerve exposure techniques in patients with cubital tunnel syndrome or osteoarthritis.10, 11, 12, 13, 14 Kovachevich et al.12 performed ulnar nerve decompression in 13 elbows with osteoarthritis using a standard posterolateral approach, or the inside-out technique. Although it has the advantages of decreased postoperative scarring and pain, faster postoperative return to life and work, and reduced neurovascular injury, this approach carries the risk of ulnar nerve palsy or injury and persistent joint contracture.
Taking an unconventional approach, we use an outside-in technique to clear the medial gutter and posterior compartment lesions. The unique anatomy of the elbow joint allows us to palpate the subcutaneous ulnar nerve, and the outside-in technique thus perfectly protects the ulnar nerve while completely decompressing the ulnar nerve and clearing the medial gutter and the posterior compartment, greatly reducing the risk of iatrogenic injury to the ulnar nerve.
Disclosures
All authors (C.Z., J-T. M., W-Y. L., S-Z.H., X.C.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Funding
This research was supported by the Henan Provincial Science and Technology Key Tackling Projects (No. 142102310082).
Supplementary Data
The lateral decubitus position is employed for this right elbow affected patient. The 2 medial portals are positioned along the ulnar nerve above and below the medial epicondyle. After the creation of subcutaneous space through blunt dissection via the 2 medial portals, the scope and shaver are introduced separately to further expand this working space. By viewing from the proximal portal, a radiofrequency device is inserted through the distal portal and advanced proximally to expose and isolate the ulnar nerve from the triceps muscle; tissue covering the ulnar nerve is removed using a shaver, thereby exposing the cubital tunnel retinaculum. The viewing portal and the working portal are then switched; by observing from the distal portal, a radiofrequency probe is introduced through the proximal portal to transect the cubital tunnel retinaculum distally; and the underlying ulnar nerve is exposed and released from surrounding tissues. The senior author (C.Z.) has described this arthroscopic ulnar nerve–exposing technique in the previous issue of Arthroscopy Techniques.
Tissue lateral to the ulnar nerve including the medial capsule is removed using the radiofrequency device. With continued switching between portals, the scope is reinserted through the proximal portal while the radiofrequency device is reinserted via the distal portal to remove additional medial capsule and expose the medial ulnohumeral joint. The elbow is extended and, using the outside-in-out technique, the switching stick is inserted from the distal posteromedial portal into and through the posterior compartment, followed by penetrating out of the posterolateral skin; the switching stick is then retreated laterally with its end elevating the triceps to form a retractor for the triceps and the posterior capsule. The posteromedial capsule is stripped off from the humerus and the olecranon, and the remnant posterior ulnar collateral ligament is resected. The medial olecranon osteophyte is trimmed with a round burr, and the capsule of the posterior compartment is removed using the shaver through the distal posteromedial portal. At this step the medial gutter and posteromedial capsule debridement utilizing an outside-in approach is finished.
By observing from the proximal posteromedial portal, the posterolateral portal is located and established using the outside-in technique. The posterolateral capsule is then carefully stripped away and excised from both the humerus and the olecranon. The spinal needle is inserted transcutaneously to retract the ulnar nerve medially, with its tip penetrating the medial intermuscular septum to create a fixed retraction medially for the ulnar nerve. The osteophyte and loose body in the olecranon fossa are removed using the round burr. The tip of the olecranon and its lateral corner are then exposed, followed by trimming the residual osteophytic overgrowth with the burr. The arthroscope is subsequently switched to the distal posteromedial portal, allowing for reevaluation of the posterior compartment debridement. The integrity of the ulnar nerve is reconfirmed with turning of the arthroscope.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
The lateral decubitus position is employed for this right elbow affected patient. The 2 medial portals are positioned along the ulnar nerve above and below the medial epicondyle. After the creation of subcutaneous space through blunt dissection via the 2 medial portals, the scope and shaver are introduced separately to further expand this working space. By viewing from the proximal portal, a radiofrequency device is inserted through the distal portal and advanced proximally to expose and isolate the ulnar nerve from the triceps muscle; tissue covering the ulnar nerve is removed using a shaver, thereby exposing the cubital tunnel retinaculum. The viewing portal and the working portal are then switched; by observing from the distal portal, a radiofrequency probe is introduced through the proximal portal to transect the cubital tunnel retinaculum distally; and the underlying ulnar nerve is exposed and released from surrounding tissues. The senior author (C.Z.) has described this arthroscopic ulnar nerve–exposing technique in the previous issue of Arthroscopy Techniques.
Tissue lateral to the ulnar nerve including the medial capsule is removed using the radiofrequency device. With continued switching between portals, the scope is reinserted through the proximal portal while the radiofrequency device is reinserted via the distal portal to remove additional medial capsule and expose the medial ulnohumeral joint. The elbow is extended and, using the outside-in-out technique, the switching stick is inserted from the distal posteromedial portal into and through the posterior compartment, followed by penetrating out of the posterolateral skin; the switching stick is then retreated laterally with its end elevating the triceps to form a retractor for the triceps and the posterior capsule. The posteromedial capsule is stripped off from the humerus and the olecranon, and the remnant posterior ulnar collateral ligament is resected. The medial olecranon osteophyte is trimmed with a round burr, and the capsule of the posterior compartment is removed using the shaver through the distal posteromedial portal. At this step the medial gutter and posteromedial capsule debridement utilizing an outside-in approach is finished.
By observing from the proximal posteromedial portal, the posterolateral portal is located and established using the outside-in technique. The posterolateral capsule is then carefully stripped away and excised from both the humerus and the olecranon. The spinal needle is inserted transcutaneously to retract the ulnar nerve medially, with its tip penetrating the medial intermuscular septum to create a fixed retraction medially for the ulnar nerve. The osteophyte and loose body in the olecranon fossa are removed using the round burr. The tip of the olecranon and its lateral corner are then exposed, followed by trimming the residual osteophytic overgrowth with the burr. The arthroscope is subsequently switched to the distal posteromedial portal, allowing for reevaluation of the posterior compartment debridement. The integrity of the ulnar nerve is reconfirmed with turning of the arthroscope.